In a world rotting from within, chain-smoking occult detective John Constantine is reluctantly drawn into a supernatural apocalypse when the ancient force known as the Rot begins consuming reality. Forced to reunite with his former lover, the powerful sorceress Zatanna, alongside the ghostly Deadman, the demon-cursed knight Jason Blood, and the enigmatic Madame Xanadu, Constantine must confront his own damnation—and the ghost of a little girl he failed to save—to stop the Lord of Decay, Anton Arcane, from plunging existence into eternal darkness, even if it costs him his soul.