You can call the Joker a lot of things—psychopathic, murderous, disturbed, obsessed, anarchic, maybe even genuinely funny. But one thing no one would call him, regardless of what side of the law you may fall on, is dependable. The Joker will double-cross his own partners on a whim, let alone anyone trying to stop him. He’s stabbed Harley Quinn in the back, played the Legion of Doom for fools and shown that he can’t even be trusted not to turn on himself (in last year’s Batman: Three Jokers). You can’t take the Joker at his word, not even when it comes to his own history. As he’s famously said, if he’s going to have a past, he prefers “it to be multiple choice.”

Yet, when it comes to solving one of the strangest, most perplexing mysteries to ever hit Gotham, the Joker’s word is about all that you have.