DS Jane Bennett takes charge of South London's Lewisham murder squad following the temporary suspension of her boss, DI Mike Lockyer. His involvement with a female witness resulted in her murder. Mike returns to work but he's a shadow of the detective he was a few months before.
Bennett gets a desperate call from an old friend to say that her husband, retired colleague Mark Leech, has gone missing. Blood spatters found in the home suggest that she doesn't have long to find him.
When Jane is sent to a site in Elmstead Woods she stumbles upon a sinister murder scene. A tomb has been created, and the body she finds is not Mark's - as she dreaded and suspected - but that of missing university student, Maggie Hungerford. Her killer recorded her last moments, even providing an air supply which was only cut off when the game lost its thrill.
Two men admit to having had a sexual relationship with Maggie. Both deny murder. Someone is lying. And Mark is still missing. When another tomb is discovered, an anonymous tip and mounting evidence suggest a disturbing link which threatens to derail both cases and let a murderer walk free.
Lockyer is shocked into supporting Bennett in a case which becomes ever more ominous and dangerous as the investigation deepens. They know that their hunt is for a killer with a mind so twisted that he, or she, is likely to stop at nothing.