Thomas Levy (Hoffman), better known as "Babe", is a graduate student living by himself in New York City. Occasionally, his brother, Henry (Roy Scheider) will stop by for a visit. Henry is a spy working for the United States government and is often out of the country for extended periods of time. After the brother of a Nazi war criminal, who possessed a safety deposit box key, is killed in a traffic accident, Henry suspects that the Dr. Szell (Olivier) will be arriving to retrieve an extremely valuable diamond collection.