The Peculiar Crimes Unit faces its most baffling case yet--and if Bryant and May can’t rise to the challenge, the entire unit may go under. Near the Tower of London, along the River Thames, the body of a woman has been discovered chained to a stone post and left to drown. Curiously, only one set of footprints leads to the tragic spot. 'The Bride in the Tide,' as the London press gleefully dubs her, has the PCU stumped. Why wouldn’t the killer simply dump her body in the river--as so many do? Arthur Bryant wonders if the answer lies in the mythology of the Thames itself. Unfortunately, the normally wobbly funhouse corridors of Bryant’s mind have become, of late, even more labyrinthine. The venerable detective seems to be losing his grip on reality. May fears the worst, as Bryant rapidly descends from merely muddled to one stop short of Barking, hallucinating that he’s traveled back in time to solve the case. There had better be a method to Bryant’s madness--because, as more bodies are pulled from the river’s depths, his partner and the rest of the PCU find themselves in over their heads.