Huganay appears in two of the boys' cases and proves to be one of the most likable of the villains encountered in the series. In "Stuttering Parrot," Huganay is in a race to beat Mr. Claudius to the lost masterpiece hidden by John Silver. He has a couple of gangster types who drive him around and act as his henchmen. Huganay is French and very intelligent. He is able to figure out John Silver's messages as quickly as Jupiter and shows up to try to steal the painting just as Jupe and Pete have discovered the hiding place in the cemetery in Merita Valley. After Jupe and Pete escape from Huganay's clutches, the boys return to Headquarters quite unaware that they have unintentionally recovered the materpiece in a piece of lead pipe. However, in a strange show of good sportsmanship, Huganay calls the boys to congratulate them and tips them off that they do have the painting.
In "Screaming Clock," Huganay is invisible for most of the story and is not revealed until after Bob is kidnapped by Jeeters. In trying to find a way to help Bob, Jupe teams up with Huganay to help rescue Bob and find the paintings hidden by Bert Clock that will clear Harry's father. Huganay is at his most charming in this story, constantly bestowing compliments on Jupiter and the Three Investigators ("ingenious organization"; "...my plump but clever young friend"; "your mind hums like a top"). After Jupiter deduces the location of the paintings and they are recovered, the police arrive on the scene. Of course, the readers expect Huganay to be taken into custody, but Huganay proves once again that he is one step ahead and gallantly steps out of the story, presumably to find another adventure down the road involving masterpieces of art.