World's Finest (2004)
World's Finest is a fan film directed by Sandy Collora. It works as a trailer to a movie that does not exist: the long-awaited cinematic team-up of Superman and Batman. While Superman and Batman have appeared together often in comic books and in animation (notably Super Friends), this fan film is the only time that the characters have been on the screen at the same time in live action. The title refers to a former famous comic series, featuring Batman and Superman working together in every issue.
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