A photo shoot in the Thames, playing dead: a corpse for the gallery walls. This is Mercy Alexander's work. Enigmatic, glamorous, beautiful - not many people know the real Mercy. She's been an image far too long. But Rose knows, her friend from childhood, her soulmate. A prostitute.

Then Rose meets a terrible death and Mercy must confront what she has long feared: that Rose has been selling herself at the city's grandest brothel, and now someone has ended her life for kicks. But the only witness to Rose's death has disappeared and Mercy must turn to someone for help who himself has much to hide . . .