“Everyone in this country is going to die anyway.”
Despite her harmless appearance, Misawa is quite ruthless. She appears to be rather kind and polite, but changes drastically when the situation calls for it, proving to actually be very rough. She has even been shown to be excessively brutal at times, such as when she hit a flight attendant with the butt of her shotgun, and then continued to beat him when he was down.
In the novel, her nature is rather different. She enjoys violence and hurting people both emotionally and physically, mainly the latter. She killed her first "victim" when she was only fifteen-years-old. Hatsune is also very short-tempered, and dislikes children, saying that she "hates the sound of kids' voices."
Misawa has chest-length brown hair and brown eyes.
Misawa is first seen with her colleagues, caring to some plants. When Daisuke Matoba stabs someone, Misawa walks over to the man's dead body and aggressively steps on it, remarking that they will all inevitably die.
Later on, Kujo and others pull up into the research laboratory. Misawa exits the car and graciously apologizes to the night guard for disturbing them at such a late hour. She begins to explain herself, but stops half-way to stab him with a knife she had hidden on her person. She also kills one of the workers in the laboratory, brutally slitting their throat. She was to go get Maki so that she could be used as leverage in order to convince Nikaido to not destroy the antidote, but Nikaido killed himself to prevent this from happening.
Throughout the rest of the film, Misawa plays a relatively minor role, providing some brute force when needed.
She makes a more significant appearance towards the end of the movie, escorting L to K, whilst pointing a gun at him. When L tries to convince K to use the antidote to help the people on the plane, Misawa tosses her gun, pulls out a knife, and takes a baby from one of the passenger's arms. She tells L that the child and everyone else on the plane can all die, but before she can stab the child the passes out due to the virus, which had spread to everyone on the plane.
When things calm down, Misawa, along with Kujo and others, is arrested.
When several members of Blue Ship confront Professor Nikaido, demanding the antidote, he refuses. Hatsune, having expected (and hoped) that he would say as much, brings out his daughter Maki, very excited with this turn of events. Maki pleads her father not to give into their demands, and Hatsune snaps at her, telling her to shut up and that she hates the sound of children's voices. Nikaido ultimately ends up dying when a member of Blue Ship shoots him in self-defense.
Later, after Blue Ship Maki gives Blue Ship the antidote data in return for Dr. Kujo's safety, Kujo turns the gun on Maki, knowing that L would not hand over the data to a child, to which he concedes, and she threatens to kill Maki if he does not hand it over. L doesn’t believe her, calling out her bluff, and Hatsune Misawa steps forward, injecting Maki with the virus so that L has no choice but to hand over the antidote. Having the information they need, the kidnappers start shooting at L and Suruga, and the two dive for cover. Suruga pleads L to use the Death Note, telling him that it is the only way, that if he can kill Kujo, the rest of the men will be too scared to try anything. L relents and begins to write down Kujo’s name. Her name is a fake, and so when Suruga sees him write down “Kujo”, it confirms that L doesn’t actually have the Shinigami Eyes.
After Maki leaves, Kujo confronts Hatsune Misawa, telling her that she was supposed to have injected L with the virus if necessary, not Maki. Hatsune says that the outcome is all the same, and mocks Kujo, asking if she developed feelings for the girl, going on to point out that everyone in Japan is going to die anyway.
L ends up leaving Hideaki Suruga behind to the mercy of the members of Blue Ship. Hatsune crouches down, taunting him, and Suruga points out that he can see her underwear, but Hatsune doesn't mind, explaining that there will be much more to see.
When Maki is held captive, L and Suruga meet Hatsune and Yoshizawa in a building, demanding the Death Note. L hands over the Death Note, and, to see if it is real, L is told to write his name down. L does so, and jumps off of the building; Hatsune and Yoshizawa look over the edge of the building and see a body on the ground (which is actually Matsuda, who disguised himself as L as part of L's plan). Now convinced that the Death Note is real, they demand that Suruga write his name down, and after much pleading, Hatsune and Yoshizawa allow Suruga to write down that he will die an hour later, but not touch any of the equipment. Hatsune crouches down and says her taunting farewell to Suruga, who again points out that he can see her underwear. Hatsune tells him to consider it a parting gift.
When on the plane to Los Angeles, things go amiss when Matoba notices that Maki is beginning to exhibit symptoms of the virus. Once it is revealed that Kujo has other plans, ones that involve killing Matoba and everyone on the ship, she, Konishi, and Robert Fairman hijack the plane. As Kujo explains her motives to Matoba and the others, revealing that she had secretly injected them all with the virus. Matoba notices that Kujo is crying tears of blood: a symptom of the virus. Matoba falls to the ground, screaming that he does not want to die. He bumps into Hatsune, who stares at him in disappointment; she had respected, even worshiped him, but now all of that was gone... Kujo points a gun at her, but Hatsune says that she can go ahead and shoot Matoba, adding "I knew all along that you were badder than the rest of us (177)." Hatsune casually walks back to her seat, humming a tune, and pulls out a magazine.
She hears a gunshot, knowing full well that her former partner-in-crime, Yoshizawa, is now dead. This has no effect on her, however. Death does not intimidate Hatsune at all; it is revealed that the first time she killed was when she was merely fifteen.
Hatsune reads in her seat for a while but notices that nothing she is reading in the magazine has really sunk in. She then recalls how she and Yoshizawa had made a good team. She puts away the magazine, unwraps her umbrella, which she has made into a shiv, and opens the emergency door of the plane. When Konishi asks her what she is doing, she explains that she is bored and wants to jump onto the wing of the plane. Konishi points a gun at her chest, but when he hesitates, Hatsune kicks him back, then kicks his gun out of the plane. Konishi begs for mercy, but she gives him none, stabbing him in the throat with her shiv, commenting that if he is going to shoot someone, he shouldn't hesitate.
Hatsune jumps onto the wing of the plane, and L eventually joins her. The two end up getting into a confrontation, and L steals her stiletto knife, which she has been carrying with her throughout the entire story, and flips underneath the wing and then appears underneath her and stabs her foot. Hatsune screams in pain and then falls off the plane.
It is unknown what Hatsune's ultimate fate is. Matoba had also fallen off of the plane, but managed to survive, though he broke many bones in his body (and it is unknown if he eventually ends up dying from this), so it is possible that she survives, though she very well may have died.
- “We die anyway.”
- “I'm sorry to disturb you so late. We have business *stabs* to take care of.”
- “You wanna shut up? *cocks gun* Not everything's gonna go as planned.”
- (to Maki) “That’s right, little girl. This lady may look shy, but she doesn’t give a damn about people's lives. She’s badder than this virus.” (novel, p 70)
- (to L) “I should have killed you when I had the chance.” (novel, p 172)