In the prologue of From Hell, two old men, former detective Frederick Abberline and psychic Robert Lees, are walking on the beach. Lees reveals to Abberline that he's a phony - he faked all of his "psychic predictions" complete with fake seizures. Abberline says that all the predictions came true, though, and this is what Lees replies:
That must have been it. I mean, From Hell is one of my favorite graphic novels ever.