Head of the Bath murder squad, Peter Diamond isn't exactly up to his elbows in bodies in the placid resort. He's bored, a bit testy, and ready for an old-fashioned mystery. Alas, when one does come along it's not in his division; it's a half-million-dollar heist by a thief who first has sent a rhyming riddle to all the local radio stations. Diamond is ready to throw his weight around to help solve the robbery, but before he can step on any toes, a body turns up and the corpse is in his court.

There's only one catch. It's impossible for anyone to have committed the crime. The victim belongs to an elite group of mystery lovers called the Bloodhounds. The body is inside a padlocked houseboat, and the only key is in the pocket of a man with an ironclad alibi. The murderer cannot logically have left the scene, yet the victim is definitely not a suicide. Has one of the other Bloodhounds decided to commit the perfect crime?

Was the heist and its verse a red herring, part of a labyrinthine plot by a twisted mind?