Cowboy Bebop: The Movie (2003)

Set on Mars in the year 2071, this film's story starts when a tanker truck explodes in a large city, releasing a deadly virus that kills hundreds. A massive reward attracts the interest of Bebop, a team of interplanetary bounty hunters, who sign on to investigate the event. Soon, they discover that the case appears to be connected to a man who had been believed dead for over ten years.