The ship rocks violently, and Gemma leans against the door to steady herself, but the figure on the narrow cabin bed doesn't move at all...

London, 1859. Nurse Gemma Tate boards the American packet ship the Prince Regent to aid Inspector Sebastian Bell in investigating the death of a British aristocrat. But when she sees the crime scene, Gemma realizes that her knowledge of human nature will be just as valuable as her medical training. Lord Anthony Blackstock lies murdered in his cabin, his head locked inside a nightmarish iron cage. His wife has vanished without a trace, and time is running out to find her, dead or alive...

Sebastian and Gemma have until the ship docks in London to uncover the truth behind the Blackstocks' final evening together. But as they unearth a web of blackmail, bitter arguments and secret affairs among the ship's guarded passengers and crew, one chilling fact becomes clear: they are trapped aboard with a killer who is growing increasingly desperate...

Love, obsession and danger collide on the murky waters of the Thames in this atmospheric mystery, perfect for fans of Anne Perry, Andrea Penrose and Miss Scarlet and the Duke.