Justice League: Crisis on Two Earths

Justice League: Crisis on Two Earths is a 2010 American animated superhero film directed by Lauren Montgomery and Sam Liu and written by Dwayne McDuffie. It is based on the abandoned direct-to-video feature Justice League: Worlds Collide, which was intended as a bridge between the DC Animated Universe series Justice League and Justice League Unlimited, and reworked to act as a standalone story. It is the seventh film of the DC Universe Animated Original Movies. The premise of Crisis on Two Earths is borrowed from the 1964 Gardner Fox Justice League of America #29–30 story entitled "Crisis on Earth-Three!" and 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.