When a madman attacks Batman with a new and powerful fear toxin, The Dark Knight visits the coldest and most distant part of his soul. And as his deepest fears resurface, he must rely on old friends to help quell the terrible effects, and to remind him of his true mission as a hero. But what Batman discovers hidden in a moment of courage may change his life forever... for a dark figure from his past has returned – the one adversary The Dark Knight truly fears.