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.

Plot

In an alternate universe, heroic versions of Lex Luthor and Joker (called the Jester) steal a device called the "Quantum Trigger" from the headquarters of the Crime Syndicate. When an alarm is tripped, the Jester sacrifices himself to allow Luthor to escape from the Syndicate. Luthor escapes to the Earth of the Justice League by activating a device that enables interdimensional travel.