One distant prison planet. Forty metahuman psychopaths.

Some thought banishing these villains - Flash's Rogues, Metallo, Vandal Savage, Killer Croc, the rest of the worst - would stem the recent violence on Earth. But Luthor seeks escape. And even with Joker's followers embracing the primal violence of the strange land, the war these two madmen will bring to one another's camps - murder, betrayal, ape-on-ape violence - is still less frightening than what's suddenly appeared in the sky.