Abbé Pellegrin, parish priest of Sableuse, sells an ancient Christ to an unknown man, M. de Saint Preux. Summoned to the bishop's palace, he learns that he has been the victim of a swindler. The Christ, exchanged for a "mouthful of bread", is a valuable antique. Not wanting to compromise his wartime comrade La Goupille, who had introduced him to Saint Preux, Pellegrin proposed to his bishop that he himself carry out the search for the Christ. For the occasion, he swapped his cassock for a "civilian" outfit and landed in Paris. He recovers the treasure in the midst of a series of adventures and misadventures involving Cousinet, the former squire of Sableuse. He takes in the tenants Cousinet has just evicted from his hotel.
