Inspired by a real espionage affair of the 1950s, this story takes Commander X to a country beyond the Iron Curtain, while Jacques D., a junior intelligence officer, sent on a mission there, proves to be not be up to the task. Commander X, a friend of Jacques, learns this news by chance and is moved by it. He decides to go there to help Jacques. Will he manage to save it? This episode illustrates a secret service process, the system of the "mailbox" that allows agents
