A newly-minted PC encounters a ghost while doing grunt work on a murder case, and soon becomes an apprentice in the magical wing of the Metropolitan Police. A series of pretty grisly incidents occur, which he realises are all part of a macabre real-world performance of a Punch and Judy show. A pretty fun and enjoyable supernatural police procedural that does some interesting stuff with the spirit and history of a city… but the main character is far too horny for me.