During World War I, the son of a British aristocrat and the daughter of an English colonel get entangled in a treacherous scheme. They must negotiate with secret agents and spies who are persuaded of their innocence. Catherine Abbeway and Julian Orden meet by chance, which leads to a complicated narrative of suspicion and government corruption. Catherine is the daughter of an English colonel and is being pursued because she possesses sensitive papers. Julian collects the documents for fear of incriminating Catherine and confirming her status as a traitor. Julian and Catherine become involved in an expanding plot driven by both English and German forces.