A young man in love with a married woman takes the husband's place in the barracks and finds his rival there. But the fact that there are two Champignols in the ranks gives rise to many misunderstandings. But the husband preferring his painting, willingly abandons his pretty wife to the lover.

Thanks to a bit of string-pulling by his aunt, Jean du Bois d'Ombelles, a young recruit who has blue blood in his veins, hopes to go through a nice and comfortable military service. Unfortunately he becomes Corporal Bourrache's pet aversion. Nevertheless, against all expectations, Jean ends up taking a liking for military life.