Son of Holmes

In 1915 Auguste Lupa, a mysterious 25-year-old chef, is asked to join the weekly homemade-beer-and-conversation sessions of undercover French spy Jules Giraud, who is on the trail of a master German saboteur with designs on the nearby armory in St. Etienne. At Lupa's first meeting with Giraud's group, a member is killed with poisoned beer. Convinced that this murder is the work of the German spy, Giraud enlists Lupa in finding the culprit. An attempt is made on Lupa's life, the armory is blown up, and the probity of the chef himself is questioned by the police before he brings all the suspects together for a confrontation and unmasking.