Justice League: Crisis On Two Earths (DVD)

In an alternate universe where evil usually triumphs over good and where the roles of the heroes and villains are reversed from their counterparts in the mainstream DC Universe, the parallel Earth is ruled by an evil version of the Justice League, and Lex Luthor is a heroic figure battling to save the planet! Luthor must fight off his universe's Crime Syndicate, a gang of villains whose superpowers are matched by those of the good Justice League, except that these malicious doppelgangers are willing to do the one thing Batman and Superman never would: kill. After activating a dimensional-travel device, Luthor escapes to the Earth of the heroic Justice League for help battling the Crime Syndicate and returns to his universe with Superman, Wonder Woman, Green Lantern, Flash and Martian Manhunter.