Jason Dean is the main male antagonist and the true main antagonists in the cult classic film Heathers. He falls in love with Veronica Sawyer, kills three students who hurt Veronica, and finally attempts to kill Veronica and blow up the school before ultimately killing himself.
J.D. is the son of Bud Dean, the owner of a demolition company known as Big Bud Dean Construction. J.D. has moved seven times before, most notably to Dallas, Baton Rouge, Vegas, and Kansas before landing in Sherwood, Ohio.
J.D.'s relationship with his father was severely affected by the suicide of his mother who knowingly walked into a building that Bud Dean had prior rigged with explosives. It appears that his life and mental state were a lot more balanced prior to his mother's death.
It isn't known if J.D. has killed prior to Heather Chandler's death. Though it is unlikely due to him appearing to be stunned and not having a plan on what to do next. Despite this, when Veronica asks if he had "done this before", J.D. does not give an answer. This line could also imply the idea that J.D. has written a suicide note before, not for someone else, but for himself.
J.D. is a handsome young man with dark brown hair and hazel eyes. His appearance is messy at times, J.D.'s usual outfit of choice is a men's flannel paired with a flannel or short sleeved button down, covered by his signature trenchcoat. He wears one silver loop earring, but is seen wearing a diamond stud in most promotional material.
From what we can tell, J.D. seemed to have had a pretty average and happy childhood before his mother's death. When the film takes place, J.D. is jaded, and cynical. making an effort not to stand out at school, as we first see him sitting in the back corner of the cafeteria. At the start of the movie, he's usually rather calm, and is more of an observer, even after Heather Chandler's death. Once He and Veronica kill Kurt and Ram, J.D. is truly able to see what he can get away with, and becomes more unhinged throughout the rest of the film. He doesn't know what to do when things don't go according to plan, and his need to be right is unshakable.
The night of the Remington University party, J.D. and Veronica sleep together after playing a game of strip croquet, and Veronica makes a comment about how she wished to see Heather Chandler puke her guts out. The following morning, J.D. and Veronica make a plan to do just that. Among other suggestions, Veronica decides to give Heather a wake-up cup of milk and orange juice despite J.D. wanting to give her a cup of blue liquid drain cleaner.
Despite Veronica telling J.D. no to his idea because Heather would never drink a mysterious blue liquid, he still fills a solid mug with the drain cleaner. While making out with J.D. in the Chandler's kitchen, Veronica mistakenly grabs the cup of drain cleaner instead of the milk and orange juice. J.D. notices, but decides not to say anything and instead suggests he carry the cup as it would go along better with their plan. J.D. tricks Heather into drinking the drain cleaner by calling her a chicken, she starts choking and falls into a glass coffee table. The duo panics and covers up the "accident" by staging it as a fake suicide. Veronica asks J.D. if he had ever done "this" before to which he does not reply.
J.D. plans Kurt and Ram's "suicide" after Kurt tells the entire student body that Veronica had given him and Ram blowjobs during their double date with Heather McNamara. J.D. convinces Veronica to forge a fake suicide note that explains that they're gay and collects "homosexual artifiacts" to plant at the scene. J.D. tells Veronica that his Grandfather had tranquilizers from WWII called "ich lüge" bullets and that they would only stun Kurt and Ram, but not kill them. She believes him, and Veronica calls Kurt, inviting him and Ram to meet her in the woods behind the school the next morning for sex. Little did Veronica know that ich lüge actually means "I'm lying" in German, and that those bullets were very real.
Veronica meets Kurt and Ram in the woods behind the school and has them strip to their underwear. She has them count up to three when they can then strip Veronica's clothes off of her. When they got to three, J.D. jumps out and shoots Ram in the throat, killing him instantly. Thinking it's all still just a joke, Veronica shoots at Kurt but misses. Kurt runs off and J.D. chases him back around to where Veronica is sitting with Ram's body. In a panic, Veronica shoots at Kurt, hitting him in the chest.
Westerburg High Bombing & Suicide
After Veronica breaks up with him, J.D. decides he is going to kill all the students of Westerburg High and comes up with an idea for a bomb after watching one of his father's demolition videos. While watching the video, his father states he put a Norwegian in the boiler room, then put thermals in the floors above to go off after the first bomb. J.D. blackmails Heather Duke with a picture of her and Martha Dunnstock from when they were friends in their childhood. He uses her powerful influence to spread a petition around the school. The students believe the petition is to get the popular band "Big Fun" to play at their prom, among various other things, but it's really a mass suicide note for when the school blows up.
The night before the bombing, J.D. stops by Veronica's house telling her parents that she plans to commit suicide and leaves a note saying "recognize the handwriting?" After going to her room, Veronica finds that J.D. left a doll hanging from the ceiling by a noose with a shirt that says 'Big Fun' on it implying that he intends to kill her. J.D. sneaks into her room with a gun later that night intending to do just that, but Veronica has her own plan. Veronica makes a noose out of a sheet, tying it around her neck and her waist to hold up her weight without actually killing her. Believing Veronica is dead, J.D. reads aloud the actual petition the students signed and leaves when he hears Veronica's mom calling for her.
J.D. plants the thermals underneath the gym bleachers and in the boy's bathroom on the day of a Friday pep rally. Veronica stops him as he is heading down to the boiler room, pulling a gun, but J.D. knocks the gun out of her hands and knocks her out. J.D. sets up more thermals in the boiler room during the time Veronica is out cold and begins a timer for 2 minutes and 30 seconds. Veronica comes to, sneaks up on J.D., and hits him with a fire extinguisher. The two briefly fight again causing the gun to be thrown across the room. Veronica manages to get the gun, shoots off J.D.'s middle finger, pries out the information on how to shut the bomb off from J.D. with only 4 seconds left to spare, and shoots him again in the chest.
Veronica, believing J.D. to finally be dead, leaves the boiler room and the school without being noticed. While walking down the schools front steps, J.D. stumbles out behind her. J.D. tells Veronica that she fucked him up pretty bad, that she has a power that he never thought she possessed, and that the slate is clean as he activates yet another bomb strapped to his chest. J.D. asks Veronica, "Pretend I did blow up the school, all the schools. Now that you're dead, what're you gonna do with your life?" Veronica replies by putting a cigarette in her mouth. The bomb blows up, lighting Veronica's cigarette, and ultimately ending J.D.'s life.
J.D. catches the eye of Veronica Sawyer during one of Heather Chandler's lunchtime polls. The two briefly flirt before Veronica is pulled away by Heather Chandler. The two meet again at a Snappy Snack Shack where J.D. buys Veronica a Cherry Slushie and talks with her some before she heads off to a party at Remington University. Later that night, J.D. climbs through Veronica's window and asks her to play a game of croquet turned strip croquet.
Veronica breaks it off with J.D. not long into their relationship due to him murdering three of their classmates. J.D. wasn't the best boyfriend to begin with either. there's an Instance where Veronica burns her palm with the cigarette lighter of her car, and instead of offer her help, or talk to her, he instead lights his own cigarette on her hot wound. There are also multiple instances of J.D. forcing himself on Veronica and making out with her in order to get her to change her mind, but this of course doesn't work, and only splits the two further apart. He continues to try to win her back with no avail and eventually decides to kill her, too. Upon getting to Veronica's house, he finds that she has already committed suicide, so he reads his plan to blow up Westerburg High to her "dead" body. The following day, Veronica finds J.D., shoots his middle finger off, deactivates the bomb, and finally shoots him in the chest, leaving his body in the boiler room. J.D. follows her outside where he finally blows himself up using the bomb he had originally intended for the Westerburg High student body.