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Justice League: Crisis on Two Earths is a 2010 original direct-to-video animated film released on February 23, 2010. It is based on the abandoned direct-to-video feature, Justice League: Worlds Collide, which was intended as a bridge between the then-concluding Justice League animated television series and its then forthcoming sequel series Justice League Unlimited. The movie project was shelved because of insufficient staff to produce the movie and the TV show simultaneously. Crisis on Two Earths was reworked from the Worlds Collide script to remove references to the TV series' continuity.

The premise of Crisis on Two Earths is borrowed from the 1964 Gardner Fox-scripted Justice League of America #29–30 entitled "Crisis on Earth-Three!" as well as the 2000 Grant Morrison JLA: Earth 2 graphic novel, with a heroic Lex Luthor from an alternate universe coming to the Justice League's universe for help against the Crime Syndicate, but it is not an adaptation of either story. The film is the seventh in the line of the DC Universe Animated Original Movies line released by Warner Premiere and Warner Bros. Animation. The film is not a DCAU production in any way, despite being based on a DCAU script, nor is it connected in any way to the previously released Justice League animated film; Justice League: The New Frontier.