An incoming missile attack, which is detected by all but one of the country's early warning stations, proves to be a false alarm. Steed finds himself attending an exclusive New Year's Eve fancy-dress party on a train. The train terminates at a remote, deserted station, and a guest is killed with an arrow.

The accidental death of a ventriloquist reveals that he had been carrying a fortune in gems inside his stomach. Steed stoops to blackmail and Emma goes shopping for ties in the search through the business community for a rich Borzoi.