Megan Fox stays foxy in the upcoming dark comedy and horror film written by "Juno" helmer Diablo Cody. "Jennifer's Body," also starring Amanda Seyfried, will be coming to theaters on September 18.

The "Transformers: Revenge of the Fallen" star plays the title character, a popular teenager whose body is possessed by a demon and begins to feed off of the boys in her high school. It's up to her plain Jane best friend, Needy (Seyfried), to stop her from killing more of their classmates.

Also starring are Johnny Simmons, Adam Brody, and J.K. Simmons.

Meanwhile, Fox recently filmed a faux public service announcement as part of the film's publicity.

In the seemingly serious fake PSA, Megan tackles peer pressure. She encourages the youth to be themselves, even if it involves "slowly killing and eating boys in your school."

"Jennifer's Body," directed by Karyn Kusama, will hit theaters on September 18.