Set in the Batman: Arkham universe, the ruthless A.R.G.U.S. director Amanda Waller assembles a team of imprisoned supervillains — Harley Quinn, Deadshot, Captain Boomerang, and King Shark — into her expendable Task Force X, planting bombs in their heads to force their obedience. Their mission: infiltrate a Metropolis under siege by the alien invader Brainiac, who has brainwashed the heroes of the Justice League into serving him. Hunted by corrupted icons like Superman, the Flash, and Green Lantern, the squad must scour the city for weapons and allies, aided by the lone free hero Wonder Woman, as they attempt the impossible — taking down the world's mightiest heroes.