Light Yagami

"If we catch Kira, he is evil. If he wins and rules the world, then he is justice."

- Light Yagami ("Justice")

Light Yagami (夜神月, Yagami Raito) is the main protagonist of the Death Note series. After discovering the Death Note, he decides to use it to rid the world of criminals. His killings are eventually labelled by people of Japan as the work of "Kira."

Appearance
Light is a young man, standing at above average height with light brown hair and brown eyes. He tends to dress very neatly and formally, often seen wearing his school uniform or a suit. He is considered to be quite handsome, a trait noted by Misa Amane and Kiyomi Takada, among others.

Character
Light is characterized as hardworking, talented, and a natural genius. Highly perceptive and good with problem solving, Light was a skilled planner and good at mapping out scenarios. Furthermore, Light was very popular among peers and adored by his family members. However, his high intelligence and constant praise from adults laid the foundation for an intense level of hubris was quickly produced after obtaining the notebook.

Similar to his father, Light has a strong sense of justice but this quickly becomes warped after he becomes tainted by the notebook’s power. Believing the world to be "rotten," he uses his Death Note as a means by which he can enact his will to rid the world of evil people. Light's main goal is to create a new world that is free of injustice and populated only with people he deems honest and kind, thus becoming the "God of the new world". Light is decisive and driven to achieve his ambitions, without faltering one bit in his beliefs. Despite knowing the criminality of murder, Light would consider his actions the ultimate “sacrifice” to help the world.

Through use of the Death Note, Light quickly begins to develop a cold and ruthless nature. As a utilitarian, he will take any means in order to achieve his goals. His actions do put his family in harm’s way, though he does continue to love them regardless. This is demonstrated when his sister is kidnapped; he prevents his father from taking drastic action as a way to keep his sister safe.

Additionally, the series shows that Light was not born remorseless. After relinquishing the notebook and losing his memories to temporarily avoid suspicion, Light demonstrates compassion, a reluctance to manipulate others and an intense unwillingness to kill. Once his memories return, however, he reverts back to his ruthless Kira persona and remains that way until his death.

The degree of Light's hubris varies by adaption. In the manga, Japanese films and musical, Light is steadfast in his decisions as Kira and rarely expresses any doubt in his actions. In the anime, however, Light reflects upon his decisions and the life he could have taken as he tries to escape capture in critical condition. The drama and Netflix film adaptions sow even more seeds of doubt in Light's character as, in these continuities, he is far less confident, is hesitant to kill and considers turning himself in numerous times. Nevertheless, Light has consistently been portrayed as an idealist and an individual is willing to go to extreme measures in order to defend his idea of justice.

History
Light grew up in Japan with his family, which consists of his father, Soichiro Yagami, who is a member of the Japanese Task Force (an investigation team opposing Kira), his mother, Sachiko Yagami, and his younger sister, Sayu Yagami.

At the start of the series, Light is a third-year high school student (12th Grade) at Daikoku Private Academy and also attends supplemental classes at Gamou Prep Academy in the beginning of the story. He later attends college at To-Oh University (東応大学, Tōō Daigaku).

Finding the Death Note
In the year 2003 (2006 in the anime), Light Yagami discovers a mysterious notebook on the ground at his school. Written on the cover are the words "Death Note". The Death Note's instructions state that if a human's name is written within it, that person shall die. Light is initially skeptical of the notebook's authenticity, but after experimenting with it, Light realizes that the Death Note is real.

After putting much thought into whether or not he should continue using the notebook, he ascertains that no one else will be able to bear the burden of improving the world. Light then meets the previous owner of the Death Note, a Shinigami named Ryuk. He explains his reasons for dropping the Death Note in the Human World, and when it is Light's time to die, he will be the one to write Light's name in his notebook. Light then tells him of his goal of getting rid of all the evil people in the world, and ruling over it as God.

L
Light's killings reach a monumental scale, attracting the attention of the master detective known as L. The first conflict between Light and L happens over the television, beginning with the broadcast of Lind L. Tailor. L places Tailor as a decoy on television in order to trick Light, with the network states that the broadcast is worldwide.

Tailor provokes Kira by calling him "evil", and, in a rage, kills Tailor with a heart attack.

Light thinks the ordeal is over, but the broadcast of Tailor is suddenly cut, and L's signature letter 'L' appears. Using a voice synthesizer, the real L announces that Lind L. Tailor was a decoy and a criminal on death row. He explains that Tailor's information was never made available to the public, so there was no way Kira could have killed him until now. L boldly taunts Kira, asking him to try to kill him, as Light stares at the TV, angrily shocked that he's been fooled. After several seconds, L learns that Kira needs the person's real name and face to kill the victim, otherwise Kira would have already killed him. L announces that the video was aired only in the Kanto area of Japan as a ploy to determine the location of Kira. L says that he is now speaking directly to Kira and tells Kira that he will catch him, then the broadcast ends.

As Light ponders over this, he accepts L's challenge to him. He also declares that he will find L and he will eliminate him. The two announce their intentions, and both declare that they are "justice", with Light needing to avoid suspicion and capture by L all while needing to kill him.

The FBI Agents
Soon after, now working with the Japanese police, L begins to lead a Task Force alongside Light's own father, Soichiro, in order to expose and capture Kira.

Light hacks into his father's computer without leaving a trace, and discovers that L and the Task Force speculate that Kira may well be a student. Light figures that considering one would be able to control the conditions of death using the Death Note, manipulating the time of death is possible as well. Light then begins killing criminals in one-hour increments in order to specifically contradict the "Kira is a student" theory, letting L know that Kira has access to police information, with Light's main goal in mind being the spawning of distrust among the police and L, as L will be bound to investigate the police now.

When walking home from school, Light is informed of by Ryuk that someone is tailing him. In order to prevent him from being investigated, Light is determined to kill his stalker.

Ryuk tells Light the purpose of the Death Note. A Shinigami gets extra life from killing humans with a Death Note, which is why a Shinigami can live for many years and cannot be killed in any other way. Then, Ryuk explains to Light that the Shinigami have eyes that allow them to see any human's real name and lifespan over their head. In addition, a Shinigami can make a deal with the owner of the Death Note to receive the "Shinigami Eyes" in exchange for half of that human's remaining lifespan, with Ryuk offering to make the deal. Light refuses the deal, stating that he needs to live for a long time in order to rule over his utopian world.

Suddenly, Light has an idea about how to find out the FBI agent's name. He decides to use his stock criminals in order to find out how specific the details of death need to be.

Light boards a bus with his date, Yuri, and Light's follower takes a seat behind the couple.

Prior to the date, Light had written the name of Kiichiro Osoerda, having him hijack the bus, then leave the bus and die of an accident after seeing a phantom. Osoreda boards the bus. The man pulls out a gun and points it to the driver, taking the bus hostage.

Light prompts his follower to say something by passing Yuri a note which contains Light's plans to apprehend the busjacker. Light asks Raye to show him proof that he is not the busjacker's accomplice, forcing him to show Light his proof of being an FBI agent, along with his name, Raye Penber. Light drops a note, which prompts the busjacker to pick it up, only for the note to have been a snippet of the Death Note, meaning the busjacker can see Ryuk. In shock, the busjacker empties his gun and exits the bus, before dying in an accident.

Back at Light's house, Ryuk asks him if he's going to write Penber's name down in the Death Note. Light tells him that it would look too suspicious if he does so immediately after they met. In addition, he wants Penber to show him the names and faces of every FBI agent sent to investigate the NPA.

On December 27, 2003, Light goes to an underground section of the Shinjuku Station. Light figured out that he can write the date and cause of death in the Death Note without a name, and the Death Note will work when the name is added later. While wearing a hood to obscure his identity, Light appears behind Penber (unaware that it is Light) and tells Penber that he is Kira. Light threatens Penber by stating that non-compliance would lead to his death, the death of his love, and the deaths of his family.

Light asks Penber if he's carrying a laptop, and if he has a file containing the names of all of the FBI agents in Japan. Penber says that he doesn't have a file like that, and Light hands him an envelope. He tells Penber to hold onto the envelope, take out the transmitter and put the earphones in. Over transmitter, Light leads Penber through a turnstile in the western entrance at 3:11 PM. Penber enters a train on the Yamanote Line at 3:13 and takes a seat. Light asks how many FBI agents there are, and Penber says that he thinks there are four groups, totaling twelve agents. Light says to call an agent that is ranked lower than him and ask for the names and faces of all agents sent to Japan. Penber uses his cell phone and calls an agent, and then asks him for the name and faces of the agents. Penber receives the FBI file at 3:21 PM, and Penber is the second FBI agent that receives it. Light tells Penber to take the contents out of the folder he gave him, and Penber takes out four envelopes with ten rectangular spaces cut out of the left side of each one. Light says to write down the names of the agents into the blocks on the folders. At 4:42 PM, when Raye exits the train, he dies of a heart attack while turning around and seeing Light.

Light takes the files home and takes the pages of the Death Note out of their envelopes, revealing the times and causes of death for each agent. Each agent will receive the file and die at a different time.

Naomi Misora
After the sudden death of Raye, Naomi Misora decides to take part in the Kira case herself. Having been told by Raye that he showed his FBI badge to someone during a bus-jacking, Naomi deduces that Kira must have been on the bus. In her attempts to contact the Japanese Task Force, she comes across Light Yagami. Light uses his father's status to his advantage, telling Naomi that he is Chief Yagami's son, which allows him to slowly win her trust. Cautious at first, she uses the false name Shoko Maki in order to protect herself until she can reach L.

After he realizes that this was an alias from the way Ryuk laughed, Light finally gets Naomi to reveal her name by saying that he is a member of the Task Force and is actually working with L. Taking advantage of Naomi's emotional state, Light gives the possibility that she could join the Task Force and help catch her fiancé's murderer. Light says that he will need to see a form of identification before she can join, and Naomi shows him her driver's license. Using a piece of the Death Note, Light writes down Naomi's name, resulting in her death by suicide. Her body is never found due to the specifications made by Light in the Death Note.

Surveillance Cameras
As Light arrives home, he finds the doorknob of his bedroom (which is usually lowered by a few millimeters) is strangely at the very top, plus the pencil lead placed on his door hinge is broken. Not only that, but his bluff, a piece of paper, was strangely put back in his door. This has Light believing that L has installed surveillance cameras and wiretaps within his room. Light then bribes Ryuk with apples, asking him to find where the surveillance cameras are.

Light buys scandalous magazines and proceeds to browse through them in order to give off the impression to L that he is a normal teenager, and that he values his privacy and that was what he was hiding all along. During dinner, L has a message appear on TV, stating that the ICPO has dispatched 1500 investigators to Japan to investigate Kira, but Light sees through this bluff.

When Light is about to study for his upcoming entrance exams, he has placed a snippet of the notebook and a mini-LCD TV within a potato chip bag (which contains a flavor which only he out of the rest of his family prefers). While studying, whenever Light places his hand in the potato chip bad, he actually checks for criminals' names using the mini-TV then writes down their names. The main idea is that L would see that criminals have died which Light could not have possibly see, being busy in his room, studying. With this trick, Light manages to kill two petty criminals.

For the next few days, Light proceeds to kill more criminals, petty or not, in order to cover up the fact that petty criminals have died solely while he was studying.

Eventually, the surveillance cameras get removed and Light plans on finding L through his father.

Meeting L
Light performs his entrance exams, when he notices a student sitting strangely on his seat.

He passes the exams, scoring perfectly, and is able to become a student of To-Oh University. Alongside another student who scored perfectly, who was the student sitting oddly earlier, he gives a speech. Noticing the strange behavior of this student, who named himself after the famous pop idol, Hideki Ryuga, Light feels annoyed at his constant chattering that concerns Light's character.

"Hideki Ryuga" then reveals himself to Light as L. Light is shocked by this and is attempting to stay calm around this supposed new friend he's made. When Light arrives home, he throws a tantrum, and explains L strategy, that should Light write down L's name using the alias even with the off-chance that it's real, the real Hideki Ryuga will die (after Light will have subconsciously pictured Ryuga's face), and suspicion will be pointed towards him. Not only that, but even if Light finds out L's real name should he take the Shinigami Eye deal, this L could very well be a proxy and suspicion from the hypothetical real L will be pointed towards Light again, as the timing will still be too convenient. Light accepts this challenge from L, getting excited over this upcoming battle of wits.

L asks Light to play tennis with him, and they do so, nearly evenly matched. During the tennis game, both of them ponder strategies. Light comes to the conclusion that L asked him to play tennis in order to lay the groundwork for future meetings which will essentially be tests as well as the fact that Light must confirm that Ryuga is L through confirmation from the Task Force.

After Light wins the intense tennis match, L reveals that he is suspicious of Light being Kira, with Light still being forced to put up the act and pretends to be shocked. They hang out together at a cafe afterward.

At the cafe, L tests Light multiple times, with Light falling for each of L's multiple psychological traps, resulting in L's suspicion of Light strengthening more and more. L asks Light to help the Kira investigation; if Light is Kira, then L will be closer to him, and if he isn't Kira, then his great intellectual ability will be of use to the investigation.

Soichiro collapses due to stress, and both Light and L visit him at the hospital. There, through Soichiro, Light manages to confirm that the L who appeared before him is, in fact, the real L.

The Second Kira
On April 22, 2004, in a broadcast on Sakura TV, "Kira" sends tapes stating that if criminal reports stop, Kira will kill police officers and reporters, and then demands that the life of someone in charge of the Kira investigation be handed over—the Director's or L's. "Kira" says to choose one and reveal them in four days and that, because Kira knows the Director's face, there are no special requirements; however, if they should choose L, he must appear on Sakura TV and give a ten-minute speech. "Kira" says that they will decide if the person on the news is L, and if it is decided that he isn't, Kira will take the lives of several police officers as compensation.

Light watches this broadcast, amused at the fact that someone else possesses a Death Note, likely with the Shinigami Eyes. Light figures this person is dangerous as they could tarnish Kira's reputation and their capture would be detrimental for Light, so Light figures he needs to join the Task Force in order to keep an eye on L as well as this fake Kira.

A few days later, L asks Light to join the Task Force. Light arrives at the hotel and appears surprised at the small size of the Task Force, and L tells Light that there are a few outsiders who know what happens within the investigation and only one can contact L directly. Light thinks to himself that if everyone in the Task Force dies but one, the killer is revealed, so he must find out who the outsider with the information is. Light is told to look over the papers of the investigation and then watch the tape without taking notes or removing anything. After watching the tapes, Light says that there may be someone else with Kira's abilities, citing the difference in criminals killed, as well as the fact that some were killed immediately after revealing their faces.

Light realizes that L would have told him his plan regardless of what he told L and that he set things up so that if Light didn't say there was another Kira, he would look suspicious, and if he did, he would help prove L's theory to the Task Force. L asks Light to help their case by pretending to be Kira and tells Light that only he is able to play this role, starting with writing a draft for the speech as Kira. Later, the tape is created and sent to various TV stations. The Second Kira responds with videos which contain indirect, and some rather direct, comments about Death Notes, Shinigami, and how they can meet. Light goes to Aoyama to find the Second Kira, but is unable to meet this Kira. However, due to having Shinigami Eyes, the Second Kira is able to identify Light as Kira due to being unable to see Light's lifespan.

After finding out his address, the Second Kira arrives at Light's house, and Light invites Misa to his room and asks her to explain her actions. Misa says that she wanted to meet Kira because her parents were murdered in front of her, and Kira killed the man who did it. Misa asks to be his girlfriend and partner, admitting that she wouldn't even mind if he simply uses her. Light agrees, intending to kill her after she outlives her usefulness. However, Misa's Shinigami, Rem, promises to kill him if he ever harms Misa.

Light has to now keep a gaggle of girlfriends so that his newfound relationship with Misa won't stand out, as L had already deduced that Kira and the second Kira have allied.

Light finds Rem to be a huge liability, as having limited control over Misa would result in her doing something reckless, which would be detrimental for Light. So, during their next meeting, Light convinces Rem to help him kill L, promising her that it's for Misa's happiness. Rem agrees to do so, and Light said that she must follow his command only when he tells her to.

At campus, Light surprisingly meets up with L again, where L steals Misa's phone after taking advantage of a crowd. Misa is then taking away, with L revealing that he found DNA evidence in Misa's room pointing towards Misa being the second Kira. This is dangerous for Light, as Misa being the second Kira would point towards Light being the original Kira.

Imprisoned
Light, now being cornered by L, puts his master plan into action. Rem had already relinquished ownership of Misa's notebook to Light, wiping her memories and preventing her from confessing.

Light then swaps the notebooks with their respective Shinigami, with Ryuk being attached to the notebook originally owned by Misa and Rem attached to Light's. Light places two fake rules in the notebook Rem is attached to, the first one being that when this notebook is destroyed, anyone who has touched the notebook will die, and, most importantly, whoever doesn't write names within the notebook within 13 consecutive days dies.

Light instructs Rem to allow Kyosuke Higuchi to become the new owner of the Death Note she is attached to, then asks L to detain him. L detains him for 50 days, and eventually releases Misa as well. During his confinement, however, Light had his memories of the notebook completely wiped.

Soichiro then fakes an execution by shooting Light and Misa with a blank gun, which makes it seem as if Light isn't Kira.

Yotsuba
Light accepts L's offer to join the investigation team to hunt down Higuchi, who has taken up the mantle of Kira. During the investigation of Yotsuba, Light works under the alias "Light Asahi".

L handcuffs him and Light together, displeasing Misa and Light. L suggests manipulating Misa in order to get information from her, but Light refuses, as he dares not to ever take advantage of someone's feelings. While Misa is resting in her hotel room, L acts lethargic about not being right, prompting Light to fight him.

Light finds a correlation between the killings and the growth of Yotsuba, having the investigation believe that Kira is either within Yotsuba or working behind Yotsuba. Keeping watch of the meetings held by the head of the Yotsuba members, Light objects to L letting the killings continue, and poses as L and decides to call Reiji Namikawa, who agreed to help L and postpone the killings.

Misa eventually finds evidence pointing towards Kyosuke Higuchi being Kira. While L and the investigation team enacts the plan to take down Higuchi, Light keeps watch of the situation and follows L, eventually to the point where he is riding on a helicopter with L, and witnesses Higuchi's arrest.

While the Task Force discovers the Death Note, Light touches it, regaining his memories as Kira once again. In order to claim ownership of the Death Note he is currently holding, Light kills Higuchi using a snippet of the notebook within his watch.

L and the Task Force then find the 13-day rule, successfully clearing Light of being suspected, while L is still skeptical.

The End of L
Light instructs Misa to find her buried Death Note, and has her trade half of her lifespan once again for the Shinigami Eyes, making the deal with Ryuk. Light then puts Misa in a situation where suspicion is pointed towards her, by having her do all the killings. This puts Rem in a situation where she would have no point but to kill L in order to save Misa, which would also result in her own death.

Of course, L's skepticism was what Light wanted, so as to have him announcing him testing the 13-day rule be the catalyst for Rem killing L, as well as the person he's closest to, Watari.

After winning the battle with L and taking his persona, Light gains control of the Kira investigation team. This puts him on the safest ground as his role as a second generation L, covering his identity as Kira.

For the next five years, by using L's database of criminal records, Light's judgments become more widespread than ever. As a result, the world falls into a dark age in which essentially everyone now lives under the law of Kira.

Mello's Kidnappings
After five years of everything going swimmingly, Takimura, the head of the NPA, gets kidnapped in exchange for the Death Note. At the same time, an FBI agent, John McEnroe, confronts Soichiro, and asks for the Death Note. This FBI agent also seeks cooperation from the Task Force to rescue Takimura from the kidnappers.

Light feels obligated to get rid of the kidnappers as well as the American organization as soon as possible, as they are currently the only people who fully know the existence of the Death Note. Light kills Takimura so that they no longer have a bargaining chip to trade the Death Note for, and it wouldn't look suspicious as one could easily assume the kidnappers killed him. However, the kidnappers then announce that they have kidnapped Sayu Yagami, which puts Light under pressure. In order to get help, he contacts the organization which John McEnroe prompted them to talk to, and Light talks to Near for the first time, who introduces himself as N and is aware of the previous L's death.

Light tells Near the current situation and Near surveils the site of the trade using satellites. The exchange went through, with the kidnappers gaining the notebook.

Near decides that he should chase the kidnappers on his own, only for his plan to fail as they had used the Death Note to wipe out more than half his team, which is when Light decided that Near must be killed. Near tells Light that someone using the nickname Mello, who is using the mafia, is behind the kidnappings, and Light has the Task Force investigate Wammy's House, letting Light know of Mello's motives more clearly.

The president calls Light, and Light figures out that Mello had blackmailed him. So, Light took advantage of this to have the president organize a raid led by Yitzak Ghazanin. Light learned the location of Mello and the mafia by taking control of the current Death Note owner and having him mail him their location. However, the raid fails thanks to the intervention of Sidoh, a Shinigami working with the mafia.

Light then had Misa send a message to the Task Force as Kira, that Kira relinquished ownership of his Death Note to one of the members of the Task Force in order to attack the mafia. Light had expected Matsuda to gain ownership and make the Shinigami Eye deal, but, unfortunately for Light, Soichiro does so instead. The raid commences and they regain the Death Note, and Light tells them to confront Mello. Soichiro threatens Mello rather than killing him, giving Jose the opportunity to shoot Soichiro severely.

Mello then blows up the base and escapes, but Soichiro had managed to give out Mello's real name to Light. Soichiro then dies in the hospital, seeing Light's lifespan absent before he died, proving to him and the Task Force that Light is not Kira.

The Battle With Near
Light selects Demegawa as the Kira spokesperson, intending to spread Kira's word in order to gain more power to take down Near and Mello. Thanks in part to David Hoope's death and the battle with the mafia, the United States submits to Kira and dissolves the SPK, the organization Near is running. Near, deducing that the second L is Kira, calls Light and claims that he has interrogated Mello, and that he learned that there are fake rules. Near disproves the 13-day rule, and gives pieces of evidence to the Task Force pointing towards the second L being Kira.

Mello contacts Mogi and tells him to follow Mello to New York, which Mogi does so under the supervision of Light and the Task Force. However, Mello had followed Mogi to the SPK headquarters, which puts Light under extreme pressure as Mello and Near are constantly pressuring Mogi into spilling information. On one hand, if Light lets Mogi live, he might spill information that would be detrimental for Light, but if Light kills him, then it'll only look worse for Light.

Luckily for Light, Mogi didn't give away any information. However, in order to kill off Near and Mogi using more conventional means in order to look less suspicious, Light sends Demegawa and tons of other Kira followers to attack Near. However, Near uses L's inheritance to distract the crowd and escape.

Near lies to the Task Force, claiming Mogi had died of a heart attack. This stirs suspicion against Light, and Near has Aizawa give Near tons of information, which has him believing that Light is Kira, while Mogi returns to the Task Force. Light now expects tighter surveillance now that Near turned the Task Force against him, so he has Misa relinquish ownership of her notebook to Teru Mikami, who kills Demegawa for running amok, testifying his worth. Mikami then selects Kiyomi Takada as the new Kira spokesperson, who coincidentally had a past relationship with Light.

Light takes advantage of this to use Takada to talk to Mikami. He does this while satisfying the Task Force, under the guise that he is investigating her. During their first meeting, Mikami calls them, and Light manages to confirm to Mikami that Light is Kira and Mikami confirm to Light that Mikami is the new Kira proxy via subtle communication. Light then says that all the Task Force's surveillance cameras and most of the wiretaps must be removed as per Kira's request. Light then privately reveals to Takada that he is Kira.

The Task Force moves to Japan, with the same being done by the SPK.

For the rest of his meetings with Takada, Light and her communicate by writing notes. Light instructs Takada to tell Mikami to forge a fake notebook and use that fake to write down names in public, while he sends Takada the real names so she does the killings. Light's incentive is that, for his final confrontation with Near, he expects Near to swap his notebook with a fake, which is why he's already preparing a fake.

Near calls Light and informs him of their ongoing investigation of Takada.

Light also Mikami say things in public suggesting Ryuk hasn't been following him. This way, when Near touches the Death Note, he won't think that there is no Shinigami because the notebook is a fake.

Near calls the Task Force and informs them of a meeting Near wants to arrange, taking place at Yellow Box Warehouse, which is just what Light had expected. However, not too many days before the planned meeting, Takada suddenly gets kidnapped by Mello. Takada successfully manages to kill Mello, while Light kills Takada using a fire to remove any evidence.

The meeting commences, and Mikami begins writing everyone's name within the notebook. The only one whose name isn't written down is confirmed to be Kira. Having prepared a fake all along, Light had expected to win, as he had thought Mikami brought the real one.

However, it is revealed to be a fake. Near reveals that Mikami had actually written down Takada's name after her kidnapping, not knowing Light did the same. This allowed Near to seize the real notebook which Mikami had used to write down her name.

Light, being exposed as Kira, attempts to deny it, but with his declaration of victory as well as the evidence Near provided, everyone is convinced Light is Kira. Light laughs maniacally, and attempts to tell them the benefits of Kira's world. However, Near responds by saying that everyone has a right to choose what they think is right or wrong, while Kira is killing people to selfishly force his own personal utopia onto everyone.

Matsuda, enraged at Light, shoots at Light multiple times, leaving him severely injured.

Manga
Light is left incapacitated both physically and mentally. Light yells for Mikami to write down the names of everyone present, but Mikami responds by asking how he is supposed to kill them with a fake notebook. This brings Mikami to the realization that Light is not "God". Light becomes increasingly distraught and begins asking for help from Misa, only to be told by Aizawa that she isn't here. He then asks for Takada and is told that she is dead. In complete desperation, Light begs Ryuk to help him by killing everyone in the room, yet Ryuk reminds Light that he is on neither side. Ryuk fulfills his promise from the beginning: he writes "Light Yagami" in his Death Note, and Light futilely asks Ryuk to reverse the process. He begins to panic, repeating in his head "I don't want to die," before the Death Note finally takes effect thus killing him.

Anime
Mikami commits suicide by stabbing himself with his pen and losing a lot of blood, creating a diversion for both the Task Force and the SPK. Although weakened, Light catches a second wind and manages to flee the warehouse. Near tells Aizawa, Mogi, Ide, and Matsuda that there is no reason to pursue Light given that there should be no more hidden Death Note pieces and Light's wounds would prevent him from getting far. Aizawa refuses to heed Near's orders and has his team follow Light. Meanwhile, Ryuk writes Light's name down when the latter finds another warehouse to hide in. As Light silently dies, an illusion of L appears before Light, mirroring a scene following L's defeat at Light's hands in episode 25.

At the end of Death Note Relight 2: L's Successors, Aizawa and Matsuda are revealed to have found the warehouse Light has fled to; their expressions of shock imply that they have seen Light's body.

Death Note
In the film, a few changes were made to Light. At the film's beginning, Light is a first-year university student studying law instead of still being a high school genius like in the beginning of the manga and anime. Light's motives differ; his boredom trait does not exist, and he instead uses the Death Note out of frustration from the perceived failures of the Japanese justice system. Light, prior to his discovery of the Death Note, hacks into the government database and finds that the government secretly acknowledges that many criminals can't be prosecuted. Light discovers the Death Note in an alley during a rainy night after encountering Takuo Shibuimaru in a club and throwing a law book into the rain in a rage. Light meets Ryuk after killing Shibuimaru. Light has a girlfriend, Shiori Akino, who attends his university. Light kills Shiori at the end of the first movie to gain sympathy from L (character) using Naomi Misora, whom he also kills.

Death Note: The Last Name
After Rem "kills" L and Watari, Light writes his father's name in an attempt to kill him, an attempt that ultimately fails. The endings of both the second movie and the manga are similar. In the second film, after being exposed as Kira, Light asks Ryuk to write the names of the team members in the book during the climax. The police shoot but do not kill Ryuk as he writes in the Death Note. Light laughs until Ryuk shows Light the Death Note, revealing that Light's name was written in the book. Light tries to stop Ryuk, passing through the Shinigami. Light dies in his father's arms, begging him to believe that he acted as Kira to put justice into practice: justice, which Soichiro Yagami had taught Light since his childhood. The film concludes one year later on Light's birthday. Sayu fetches Soichiro and says that Kira helped reduce crime rates. However, she says that she does not support Kira as Light was killed by Kira (which is what Soichiro told her). Light is portrayed by Tatsuya Fujiwara, known for his role as Shuya Nanahara of Battle Royale.

Conception of Light in the films
Shusuke Kaneko, director of the film, intended for Light to appear sympathetic at the beginning of the film; when Light first gains the Death Note, Kaneko "was careful" to have Light react in a manner "as you and I would." Kaneko changed the story involving Light gaining his first notebook as he felt that the audience "would have a hard time sympathizing" with Light if the scene remained the same as it was in the manga. Kaneko added that as he portrayed Light as "being enthralled" as he "becomes more cruel" to make the audience members feel that they could "do the terrible things he does" even if the members do not sympathize with Light.

Kaneko designed Light's room to reflect the character's personality by making it clean and neat and filling it with legal, criminal history, foreign, and academic books. The original version of Light's room included a stereo; Kaneko replaced it with a vacuum cleaner to reflect Light's "clean-freak self."

Tatsuya Fujiwara said that he felt difficulty portraying Light in the film series because of the lack of "action" and because Light has no signature mannerisms and therefore has his feelings displayed by his face; Fujiwara added that he struggled conveying Light's "incredible amount of intelligence" and that the performance would appear "very empty or simplistic" if Light received an improper portrayal. Fujiwara explained that he wanted Light to cry in a particular scene even though Kaneko told Fujiwara "Light doesn’t cry" since Fujiwara believed that the scene would feel "more honest"; Kaneko used the take. Fujiwara said that he "could understand" Light's intentions to create a new world even though "murder is a horrible thing."

Television drama
Light receives major character changes in the Japanese drama. At the beginning of the series, Light is an average college student who works part-time at a pub. Light wishes to become a civil servant and shuns the idea of becoming a police officer. He is also a fan of Misa Amane, and he regularly attends her concerts. He is far more prone to emotional outbursts compared to his manga counterpart, often crying when he feels cornered by L.

Due to his decreased intelligence level, Light proves to be much less competent as Kira than his other counterparts. For instance, instead of mining data about the Kira Investigation from his father's computer, Light simply asks Matsuda or his father about details pertaining to L and the investigation. His plan to kill Raye Penber and the FBI agents is also botched when the latter sees through the plan.

Over time, however, this incarnation of Light adopts more traits from his manga counterpart, becoming more ruthless and demonstrating a cerebral side to his character. By episode 6, Light's plans demonstrate intricacy that is close to his level of intellect in the manga. Nevertheless, Light continues to periodically act carelessly on his emotions and this leads to his eventual capture by police. He is eventually killed in a fire set by Teru Mikami in a failed attempt to escape arrest.

The Musical
Light is very similar to his canon self in the musical, and the story approximately follows canon up through Misa's confinement. Light does not volunteer for confinement, and the final confrontation with L happens soon after instead. Believing that Light can no longer entertain him after he has eliminated L, Ryuk kills Light in the final scene.

Light is portrayed by various actors for the different musical productions. Kenji Urai (浦井健治) and Hayato Kakizawa (柿澤勇人) shared the role in the 2015 Japanese production, and they will both reprise the role for the 2017 Japanese production. Hong Kwang-Ho (홍광호) portrayed the character for the 2015 Korean production, and Han Ji-Sang (한지상) is taking over the role for the 2017 Korean production. Jeremy Jordan voiced Light for the English-language 2014 New York studio demo recordings.

Light performs the following songs in the Musical:
 * "Where is the Justice" is sung by Light and his high-school classroom. Light also sings the first reprise after embracing his role as Kira.
 * "Change the World" is the song he sings when he jokingly writes a criminal's name in the Death Note for the first time.
 * "Death Note," aka "Hurricane," is the song Light sings once he realizes he has killed someone with the Death Note.
 * "Don't Cross That Line" is a song Soichiro sings about his disapproval of L's methods with Lind L. Tailor. Light joins in as well.
 * Secrets and Lies
 * "Stalemate," aka "A Game of Death," is a song between L and Light at the Todai University entrance ceremony. Misa also joins in for a verse.
 * "Playing His Game," aka "Into Him," is a song between L and Light during their tennis match.
 * "Last Moments" is a song between L and Light during their final confrontation.

2017 American film
In Netflix's American Death Note film, Light's name is changed to Light Turner and he is played by Nat Wolff.

Similar to the television drama, Light's intelligence is significantly toned-down and he is portrayed as an average high school student with standard academic ability, albeit skilled enough to be able to complete other student's homework assignments for pay. Unlike his manga counterpart, this Light is not as confident and is unwilling to kill law enforcement.

He also demonstrates a willingness to use the notebook for personal gain, shown when he murders a criminal live on the internet news in order to impress his love interest, Mia Sutton (based on Misa Amane). Nevertheless, Light still has a strong sense of justice in this adaption and, with encouragement from Ryuk and Mia, begins using the notebook to create a utopia. He adopts the name "Kira" as a way to throw off law enforcement into thinking he is Japanese.

Interestingly, Mia emulates the ruthless qualities that originated from Light's manga counterpart such as a willingness to kill law enforcement to protect their identities as Kira. Light eventually kills Mia after she attempts to steal the notebook from his possession, but this lands Light in a coma and in the hospital. After he awakens from the coma, Light's father (named James Turner in this adaption) confronts Light after deducing his identity as Kira. Light's fate at the end of the film is unknown.

Conception
The following information is from Death Note 13: How to Read.

Tsugumi Ohba: Writer

Takeshi Obata: Artist

Overview
Ohba said that Light was "a young man who could understand the pain of others" when he first encountered the Death Note. Ohba said that if Ryuk never developed an interest in the human world, Light would have become "one of the greatest police leaders in the world" who, with L, worked against criminals. Ohba described Light's life as "ruined" once he obtained the Death Note, and that Light became a victim of the Death Note "in many ways". Ohba described Light as bearing good faith intentions and having a "very conceited" nature. Ohba also describes Light as having a "warped" "desire to be godlike," bearing love for his family, and intending to transform the world into "a better place". Ohba added that he believed that debating whether Light's actions were good or evil is not "very important." Ohba says that he personally sees Light as a "diabolical" character.

According to Ohba, Light sees Misa Amane, who he uses as an accomplice, as a "bad person" who killed people, so he acts emotionally cold towards her and manipulates her. Despite this, he keeps her alive even after her memories of being Kira have been removed for the second (and final) time.

Ohba said that his editor suggested the family name "Yagami" for Light. Ohba said that he did not feel "too concerned" about the meaning of the name (the kanji are "night" and "god"); he said that after he created the final scene in the manga he "liked" that the final scene created "deeper significance" in the name.

Design
Obata said that he had "no trouble" designing Light as the character description presented to him, "A brilliant honors student who's a little out there," was "clear and detailed." As the weekly serialization continued, Obata simplified the design by unconsciously removing "unnecessary" lines and felt that he became "better" at drawing Light. When Chapter 35 appeared and the editor informed Obata that Light lost his memories, Obata felt that he had to "forget everything he learned" and draw Light in a similar manner as he appeared in Chapter 1.

Obata said that he used "a lot of effort" to design Light's wardrobe. According to Obata, he encountered difficulty imagining the clothing of "a brilliant person," so he looked through fashion magazines. Obata envisioned Light as a "smart and formal guy" who wears formal shirts. Most of Light's clothing in Death Note is "fitted" and Obata avoided jeans.

When designing color book covers, Obata assigned colors to characters to "get the atmosphere right." Obata assigned clear or "lack of a color" to Light.

When asked about which character was most similar to himself, Ohba indicated Near and "maybe Light." Regarding Light, Ohba cited "because I did well in school." Obata said that Light was his second favorite human character and that he was not sure whether that was because he "liked" Light or because he drew "such a diabolical character" in a magazine for children.

Trivia

 * The name Yagami literally means "night god."
 * Light is portrayed in a crucified-like position on the twelfth and final manga cover. This position is mimicked by Light during the second ending sequence in the anime and again when he is portrayed as a secret Nendoroid figure for the Death Note Case File merchandise line. This position connects to Light's desire to be a Messiah figure of the human race similar to the Christian Messiah, Jesus Christ.
 * In the anime, certain characters take on stylized hair colors while the viewer hears their thoughts; Light's color is red.
 * In Death Note Relight 1: Visions of a God, an unnamed Shinigami appears in the Shinigami Realm. This new Shinigami asks the others where the Rogue Shinigami named Ryuk is. Some members of the fanbase believe this unnamed Shinigami to be the reincarnation of Light Yagami (more information about this can be viewed on the Myths page or on the Light's Reincarnation Theory over at the Death Note Fanon Wiki).
 * Light is one of the Death Note characters that were made into Nendoroid figures. The Light Nendoroid comes with small Death Note and a pen which he holds and three faces: a laughing face, an angry face, and a normal face.

Quotes

 * “I'm going to make the world know I'm here… that somebody is passing righteous judgement on them.” (Chapter 1)
 * “I will reign over a new world.” (Chapter 1)
 * “"I'll make you trust me. And when you've told me everything I need to know, I'll kill you.” (Chapter 19)
 * “You can't ever win if you're always on the defensive, to win, you have to attack.” (Chapter 20)
 * (To Ryuk, regarding the Death Note) “I've never considered finding that notebook and gaining that power a misfortune.” (Chapter 22)
 * “This… is the first time that I actually want to punch a girl.” (Chapter 31)
 * “I'm going to get more intimate with Misa and make her fall helplessly in love with me.” (Chapter 32)
 * “The thing I hate the most is to trample on other people's good will.” (Chapter 37)
 * “Exactly as planned.” (Chapter 53)
 * “Follow the teachings of God and receive his blessings, and so it shall be that the seas again become bountiful.” (Episode 1)
 * “I'll solve equations with my right hand and write names with my left. I'll take a potato chip… and eat it!” (Episode 8)
 * “Under normal circumstances, humans should have continued to evolve as the greatest creatures upon this earth, but we were actually regressing. A rotten world. Politics, law, education… Was there anybody around who could correct this world? But someone had to do it.” (Episode 37)
 * “I understood that killing people was a crime. There was no other way! The world had to be fixed! A purpose given to me! Only I could do it. Who else could have done it, and come this far? Would they have kept going? The only one… who can create a new world… is me.” (Episode 37)