Jennifer's Body is a 2009 black comedy and horror film written by Diablo Cody. The film is directed by Karyn Kusama and stars Megan Fox, Amanda Seyfried, Adam Brody and Johnny Simmons. Fox portrays Jennifer Check, a newly possessed teenage serial killer specializing in "offing" her male classmates as best friend "Needy" Lesnicki, portrayed by Seyfried, strives to stop her. The film premiered at the 2009 Toronto International Film Festival and was released in the United States and Canada on September 18, 2009, with an R rating in the U.S. and a 14A rating in Canada. The title is a reference to a song from Hole's album Live Through This. Another song from the album, "Violet", is played over the end credits. As a tie-in to the film, Boom! Studios produced a Jennifer's Body graphic novel, released in August 2009.

Working with Cody again following their collabrative efforts on the film Juno, Jason Reitman stated he and his producers "want to make unusual films". Cody said she wanted the film to speak to female empowerment and explore the complex relationships between best friends.