Tension mounts as Ned and Sasha are forced to work together when the body of a film critic found in a sewer is thought to be linked to the 20-year-old murder of a concept artist, David Straka. As the team interview Straka's contemporaries, groupies and assistants, looking for possible connections between the deaths, they find themselves immersed in the macabre world of the occult. And Griffin's expert knowledge of the history of London and in particular the hidden Fleet River, proves invaluable.