Batman and Superman find themselves teamed up when Lex Luthor begins his operations in Gotham City to take down his arch-nemesis, and employs a horde of the Batman's villains to do so.

Batman and Robin must battle Superman, who is under Lex Luthor's mind control, as the villain plans to launch a wave of robots and take over the world's armies.

The super-powered members of the Justice League begin disappearing one by one. Only Batman and Green Arrow are left to investigate and discover that old enemies are involved.

The heroes fight their android counterparts to recover the Justice League's powers, while the Joining prepares for its final assault on Earth.