第 1 季，第 3 集: Tuppence ponders the cryptic message she discovered in the Soho den at the end of Episode Two, and worries about Tommy who, with his cover blown, is being driven to a remote location by Brown’s gang. Tommy’s given a job to do for Brown on pain of the death of his son, George. He must steal a specific file from under Major Carter’s nose on the Third Floor, he succeeds, with Tuppence’s help, but they redeem themselves by solving the mystery of the location of the secret recording that will identify Brown. But before they can listen to it, it’s ripped from their grasp by Jane Finn’s uncle Julius, who had appeared their friend until now. When Julius claims to be Brown, our heroes smell a patsy and must penetrate Julius’ lies to reveal Brown’s identity, find out where he’s keeping Jane Finn, and foil the potential assassination of a visiting American dignitary of incredible importance to the British government.