The Eisner-nominated creative team of writer Jeff Lemire and artist Andrea Sorrentino (Green Arrow, Gideon Falls) reunite for a psychological horror story that delves into the bottomless insanity of The Joker. Everyone knows The Joker doesn't have the most promising history with psychotherapists. In fact, no one's even been able to diagnose him. But that doesn't matter to Dr. Ben Arnell; he's determined to be the one to unravel this unknowable mind. And there's no way The Joker could ever get through the therapeutic walls Ben has built around himself. Right? There's no way The Joker's been entering his house at night…right? There's no way The Joker has stood over his son's bed and put that book in his hands, the one with the, the, the… Collects Joker: Killer Smile #1-3 and Batman: The Smile Killer #1.