Young Anne Beddingfeld came to London with a small inheritance and a taste for travel and adventure. She gets more than she bargained for when a nearby stranger falls from the tube platform and is electrocuted on the rails. A man in a brown suit examines the body, but flees before the police arrive. It was an accidental death, but Anne is still intrigued. Why did the dead man startle? Why did he have a note regarding an empty house owned by a high-ranking government official? Who was the man in the brown suit who examined him and fled? What is the secret in the cryptic message he left behind: "17-122 Kilmorden Castle"?The mystery deepens when a woman is found strangled in the empty house. Anne's investigation leads her to a cruise ship heading for sunny South Africa, followed by a treacherous journey into Rhodesia. Anne encounters danger, daring escapes, romance, and uncovers a conspiracy that could shake the foundation of the British Empire.