American journalist Mary Prescott is returning from a trip to a Communist state behind the Iron Curtain, traveling with a letter of safe conduct from that nation's President. Riding on the same train is Jan Gubak, capt...展开ain of the country's soccer team and a national hero. Gubak visits the journalist in her compartment, asks her to dinner, and later persuades her to take a watch across the border for him, telling her that he plans to sell it to pay for an operation for his sister. She is then shocked when, at the border, Gubak himself reports her as a smuggler. She undergoes interrogation, while trying to determine whether there is anyone she can trust.