By luck, the cloth was unusual enough for Maigret to soon put his hands on the likely suspect, Marcel Moncin, an interior designer, who'd grown up in Montmartre. Jusserand identifies him, but he refuses to confess. And then, the day after his arrest, there is another murder. But this time Maigret understands. It was either Moncin's fiercely possessive mother, who still lives in Montmartre, or his wife, Yvonne Moncin. He brings the three to his office for a final confrontation, and though the mother confesses, to show her great devotion to Moncin, it was in fact Yvonne who'd murdered a girl to put the police off the track. Maigret says that while Moncin will no doubt spend his life in custody in some hospital, his wife will be regarded as a cold-blooded murderer of an innocent girl.