Inquisitor Collins and Proctor Dooley are two of the Church’s best investigators in a London where the police force is a Holy Order and the courts are eccesiastical, but they’ve been handed a tough case this time. The murderer had no connection to his victim that they can find. He turns out to be a serial killer, but one that paradoxically knows his victim intimately, for he kills the same person, over and over, across all the parallel worlds. Now all they have to do is find him, somewhere in them.