Cowboy Bebop: The Movie, known in Japan as Cowboy Bebop: Knockin' on Heaven's Door , is a 2001 Japanese anime science fiction action film based on the 1998 anime series Cowboy Bebop created by Hajime Yatate. Several staff from the original series worked on the film, including director Shinichirō Watanabe, writer Keiko Nobumoto, character designer/animation director Toshihiro Kawamoto and composer Yoko Kanno. The Japanese and English voice casts also reprised their roles from the series. It is set between episode 22 and episode 23 of the original series. The plot centers on a mysterious terrorist planning to exterminate the human population of Mars by releasing a virus. The bounty hunter crew of the spaceship Bebop works to capture the terrorist and prevent the attack.