The French Riviera, 1956. Erich Mielke, deputy head of the East German Stasi, has turned up in Nice, and he's calling in a debt. Mielke wants Bernie go to London with the vial of Thallium, to poison a female agent they both have had dealings with. Friedrich Korsch, an old Kripo comrade now working for Stasi, is there to make sure Bernie gets the job done. As Bernie bolts for the German border, he recalls the summer of 1939, when the body of a low-level bureaucrat was found at Hitler's mountaintop retreat in Obersalzberg. Bernie and Korsch have one week to solve the murder.