Synopsis: The Doctor lands the TARDIS in Nazi-occupied Paris during World War II. Captured by the Gestapo, the Doctor becomes the guinea- pig of Professor Schmidt who intends to try out a new truth serum on him. Fortunately, the Doctor is able to turn tables, submitting the Professor to his own drug. The Doctor learns from Schmidt that the Reynard Resistance group has been infiltrated by a Nazi Spy. The Doctor makes contact with the resistance with the intention of alerting them to the spy in their midst. Unfortunately, convincing them that he himself is not a spy proves to be more difficult than he had anticipated.
Notes: Countdown #104
Also returns as a Fourth Doctor story in 1977's Doctor Who Winter Special.