March, 1938. Otto Lehman arrives in New York by ship and is immediately picked up by two men with FBI badges - except that is not his real name and the men are not really FBI. The next day Lehman is discovered in an abandoned warehouse, tied naked to a chair and beaten to death. The only witness, a homeless man, said the two men spoke German. Counter-intelligence agent Jacob Welker is handed the investigation and he will recruit several civilians to help thwart a suspected Nazi terrorist attack. This will include Lord Geoffrey Saboy, a British 'cultural attache', and his wife Lady Patricia. They just have to first determine who the Nazis are and then what they are about to attack.