| Monsieur Dubuque |
|Behind the scenes|
|Appearances||"The Naval Treaty" (mentioned)|
Monsieur Dubuque was a French detective associated with the Paris police. He is mentioned by Watson in "The Adventure of the Naval Treaty", but in connection with another of Sherlock Holmes' cases: "The Adventure of the Second Stain", which Dubuque had unsuccessfully tried to solve prior to Holmes' involvement. Holmes gave Dubuque and Fritz von Waldbaum, a German specialist also working on the case, an interview after Holmes had solved it, where he expounded the correct solution and showed them that both had wasted their energy on side-issues rather than the facts of importance.