The Canal Saint-Martin bistro and its absent owner
Bargemen drag a man's arm, then other dismembered parts, from the Canal Saint-Martin in working-class Paris. Maigret drifts into a nearby bistro on the Quai de Valmy run by Omer Calas, whose wife Aline sits silently behind the counter, drinking steadily and claiming her husband is away on a trip. The corpse proves to be Calas, killed by Dieudonné Pape, Aline's quiet lover of many years, and the case is broken less by forensic proof than by Maigret's slow grasp of the three-way arrangement the neighborhood had quietly accommodated.