The Case of the Dangerous Robin S01 E06 Savage Street (aka Man in the Shadows)

Robin goes to Paris to try to find two highly insured emeralds belonging to Caroline Agoura, which ostensibly went overboard with her late husband, Paul. By working with Tou Tou, a clumsy Parisian second-story man, Robin learns that Agoura is not dead, is a vague but notorious smuggler, who uses the emeralds as collateral for his deals.