Through Nina, Lecoq had arranged a meeting between Bertomy and Madeline, and satisfied himself that the girl was whole-heartedly and devotedly attached to her uncle’s cashier.  Then why was she favouring the suit of the count?  Lecoq at once made it his business to inquire into the count’s past.

He was the second son of an old and noble family.  His elder brother, Gaston, having to fly the country in consequence of causing the death of several men, he had inherited the property.  A life of dissolute pleasures had soon exhausted his patrimony and he was reduced to living by his wits.  Some weeks before the robbery, he had discovered that his brother Gaston was alive and was living on a large estate in the south of France, which he had purchased with the wealth he had accumulated in business.  Six weeks after the two brothers met again, the elder died and the younger inherited his vast fortune.

Raoul de Lagors was the next character in the drama whose past the detective made it his business to expose.  Lagors, it has been said, was the nephew of Madame Fauvel.  To his surprise, Lecoq discovered, by inquiries in her native place, that the banker’s wife had never had any brothers or sisters.  Lagors, therefore, was not her nephew.

Fanferlot, acting on instructions, had kept a strict watch on the movements of Madeline, and by this means Lecoq received timely warning of a mysterious excursion which the girl made one night.  He followed her to a lonely house on the outskirts of the city.  When she had gained admittance, the appearance of a light in one of the windows on the first floor seemed to indicate the room to which she had been taken.  By the aid of a ladder, Lecoq was able to watch what was going on within through the shutters.

He saw Madeline standing opposite Lagors, evidently, from her attitude, pleading with him.  For some time he listened to her, with a cynical smile upon his face, but after an hour he seemed to decide, with evident reluctance, to comply with her request.  Going to a cabinet, he took out a bundle of pawn tickets and flung them on the table.  Hastily going through the collection, she selected three, and concealing them in her dress, left the house.

By following her to a pawnshop, Lecoq discovered that she had redeemed certain valuable articles of jewelry belonging to Madame Fauvel.  Lecoq knew, through Nina Gipsy, who still filled the part of lady’s-maid in the Fauvel family, that M. Fauvel had insisted on his wife accompanying him on the following evening to a great fancy-dress ball which was to be given by one of the wealthiest families in the capital.  Obviously, then, the jewelry that Madeline had redeemed was required by Madame Fauvel for the occasion.  Why had she pawned it for Lagors?