Two friends, Tricoche and Cacolet, are partners in a detective agency. Chance has it that Cacolet is hired by Van der Pouf, a rich banker who wants him to watch over his wife Bernardine while the latter, on her part, seeks the services of Thicoche.

Good-natured and devout, a French house painter takes the train to Rome, where he has decided to go on a pilgrimage. There he meets a scatterbrained dresser who has been assigned by a music hall star to bring her the gown she is to wear on stage. The two men get stolen by Cleo, a charming thief. Once in Rome, the painter finds himself penniless and the dresser without the gown...

Auguste, a somewhat simple-minded Provençal fisherman, loves and admires Mireille. This concerns only Maurice, son of an important wholesaler, whom scruples do not stifle. Seduced and abandoned, Mireille moves Auguste who tries to mend his poor happiness. The local priest, with wise words, leads Mireille to offer her hand to Auguste.

Following a broadcast on the radio, each of the listeners remembers these "little nothings" (the title is borrowed from a play by Mozart), which have often changed their lives. Each of these stories told will prove that a tiny detail in life can change an entire destiny.

Désiré Le Sec has just won the "amateur policeman contest" and he is so glad he 's telling all the people around.He is an insure agent ,and his boss,his uncle,is annoyed :a man took out a big life insurance and died soon afterward.

Fernand Espitalion is miserable as totally whipped husband of a dragon 'passed on' -like cloths- by his late cousin. She often leaves him waiting outside like a dog when she does business. While she sees a notary about an inheritance, he's seduced to a bar by a shady man. The rogue gets Fernand drunk, knocks him out and switches costumes and papers. He's now Robert Durand, a voluntary Foreign legion recruit. After failed attempts to explain, he tastes military life and finds it less disciplined and more enjoyable then, marriage. But will that last when his wife tracks him and his unit is sent to action in tribal Algeria?

Sénéchal, an actor touring the provinces with the "Tournées Carlini" does not meet the success he thinks he deserves. One night in Dreux, he finds himself without his luggage and dressed up as a Foreign Legion officer, he is invited to a party thrown by a colonel. He creates a sensation there and does not leave the colonel's wife ... indifferent! Back in Paris, Sénéchal goes through a similar experience. This time around, wearing tuxedo and top hat, he gets mistaken for a diplomat and charms the guests of a wedding party. Arrested by the police, he chooses to do without an attorney at his trial and his brilliant eloquence has him acquitted. A question remains unanswered though : will all those people who give an ovation in real life ever go to see him on stage ?

Émile Boulard is a props man in a Paris movie studio. He has a wife, Suzanne. Or to be more accurate, let's say he HAD a wife since she left him fifteen years before, allegedly ... to go buy a post stamp. But now that their daughter Martine , who lives with her, is old enough to marry, she resurfaces. She confesses that, in order to explain his absence, she has told Martine her father was a great explorer and lion hunter in Africa. Not to disappoint his daughter, Émile accepts to pose as the adventurer he is supposed to be. At the same time he will help Daniel, Martine's bashful fiancé, not to become a henpecked husband like him.

Hercule, a young peasant, inherits a Parisian newspaper with a large circulation. The editor-in-chief, Vasco, takes advantage of his ignorance to make corruption prevail. But Hercules gradually realizes the role that we make him play.

For 25 years now, under the Provence sun, Antonin, a farmhand, has shared his work and everyday life with a horse named Ulysse. What a shock when Pascal, the farmer, tells him he has decided to sell Ulysse to a picador for being too old. Not only will he be separated from his faithful companion, but he is well aware too that the arenas of Arles mean death for Ulysse. Being unable to stand such injustice, Antonin runs away from the farm in the company of Ulysse. Together, they go through the Lubéron, the Baux de Provence, the Alpilles, the Crau and the Vaccarès. Yet, their journey is no pleasure cruise, specially when it comes to crossing National Road 7. After a visit to Marcellin, an old friend of his, Antonin sets off again with Ulysse, this time towards the Rhône River.

Guillaume Dodut is a stationmaster in rural France at a station where trains no longer stop. His dream has always been to holiday in the famous resort town of Biarritz. Meanwhile, he gets involved in the romantic life of his son who is studying to be an engineer in London.

Lafraise and Plumard, two rookies on the ship Le Victorieux, are on leave in the port of Toulon. At a time they get lost and in order to escape the Navy patrolmen, they disguise themselves and board a train. Now it happens that in the convoy a delegate of the government is on his way to Paris, with the mission to inaugurate a monument there. But the circumstances are such that our two friends are mistaken for the Minister and his secretary. Unabashed, the pair does the job, in other words, they deliver the expected speech, eat like horses, live it up - until they are recognized. Which eventually results in a prolonged stay in an unpleasant kind of hotel room named - the hold.