Just demobilized, Pierre Larrieu and his friend Jacques Arvel have put up at the Pension Robinet in the Beauce region. Unfortunately, they are now penniless, which makes the owner of the hotel beside himself. Good for them, his sister Sabine Robinet, a much more lenient person, secretly helps the poor chaps to survive. Pierre, who is supposed to inherit his late uncle's fortune, finally receives a letter from his notary telling him that he is the happy recipient of ... 192 francs! Devastated at first, Pierre soon understands that his uncle must have hidden the loot somewhere in his farm. So, when he learns that the new owner of the "Ferme des Sablons", an eccentric inventor by the name of Horace Rouvière, is looking for a married couple to take care of the house, Pierre grasps the opportunity: he asks Jacques to disguise himself as a woman and, no sooner said than done, they ring the farm doorbell ...