Asked to advise on the antiques collection of a mysterious widow, Arnold Landon enlists the aid of an old friend, Carmela Cacciatore. He soon finds himself drawn onto the investigation of an antiques smuggling operation which leads to murder and the hunt for an ancient religious manuscript looted from the Baghdad Museum. But despite these exotic connections, it is back in chilly Northumberland that Arnold finally learns the truth and faces the deadly menace of the Shadowmaker...