A mysterious message leads Sidney and Melinda to a railway locker at Victoria Station, where a golden key opens the way to a hidden warehouse filled with crates of elephant ivory. An old photograph of three British soldiers reveals a sinister connection between Melinda's father, a dead officer named Barton, and the elusive Captain Edward Buck. As Sidney investigates, assisted by his courageous companion Moira Hunter, the discovery of stolen military documents exposes an international smuggling and espionage network. Gunmen attack, Moira is seriously wounded, and Sidney and Melinda must continue their dangerous mission alone. Their pursuit leads from Whitehall to the London docks and finally to a riverside mansion in Greenwich, where a dramatic confrontation brings the conspiracy to a violent end. But danger is not the only thing Sidney discovers. His growing affection for Melinda complicates his already adventurous romantic life, particularly when Moira makes an unexpected return from hospital. A thrilling Edwardian adventure of espionage, murder, hidden treasures, dangerous secrets and romance, featuring the irresistible Sidney Orebar.