Supervillains Harley Quinn, Bloodsport, Peacemaker and a collection of nutty cons at Belle Reve prison join the super-secret, super-shady Task Force X as they are dropped off at the remote, enemy-infused island of Corto Maltese.

As a war between humankind and monstrous sea creatures wages on, a former pilot and a trainee are paired up to drive a seemingly obsolete special weapon in a desperate effort to save the world from the apocalypse.