Love at Sea is a story of a young sailor who falls in love with a secretary at a naval base. Their secret affair takes place during a long-distance relationship, bringing out the challenges of first love and the constraints of the military. The film is set against the backdrop of the French Navy and explores the complexities of boy-girl relationships in a naval environment.

Jeanne looks back on her love for Jean. The melancholic young man wouldn't accept the world as it was, always wishing to depart. She doesn't know that he's dead.

To conceal his nighttime infidelity from his wife Gisele, Pierre calls in a particularly shady private detective to concoct an alibi. He is introduced to a certain Robert Crémieux, who will pass himself off to Gisèle as a childhood friend with whom he spent the night until the early hours of the morning. The so-called childhood friend turns out to be a delinquent accused of burglary and rape on the very night he was supposed to be with Pierre. Pierre is immediately suspected of being his accomplice and, trapped by his own turpitude, arrested. Entangled in his lies and denials, he has to admit his infidelity to get out of the impasse.

Three old friends meet again. They compare their marriages and tell each other stories which illustrate why they complain about their wives.

The practice of Dr. Julien, a GP of Marseilles, consists mainly of drug-addicts. One day, one of his patient dies at his surgery and Julien yields to the temptation : he steals the dead man's money and hides the corpse in a trunk. But the whole thing is discovered and ... misinterpreted. The doctor is condemned for killing the junkie and sent to the Cayenne convict prison, from which he escapes. The Indians give him shelter and he is soon given the opportunity to return their good deed when a yellow fever epidemic strikes their tribe. A young woman helps to fight the disease and, thanks to her, Julien starts considering that a new life is possible for him.

Smalltown confectioner Lespinasse, hopeful of being reelected as chief councillor, is opposed by Darcepoil, the local druggist. Darcepoil arranges for the incumbent's defeat by having Pantaflon, a nightclub singer, lure him to the nudist camp on the Isle of Levant, where Lespinasse is photographed surrounded by half-naked women. At home, he is berated by his wife and thrown out of office; but he returns to Levant with the penitent Pantaflon and is welcomed by the nudists and voted camp president. His forgiving wife follows him and herself becomes a nudist.

Eugène, who works for Radio-Europe, is a bit dim-witted. He lives in a block of flats whose caretaker is Madame Motte, and the lady is in love with the young man. Just for laughs, Eugène's friends circulate on the air the rumor that Eugène has inherited millions of francs. It does not take long before a swarm of 'friends' start mixing with him. After a while, considering that the joke has lasted long enough, the jokers reveal the truth. Eugène immediately loses all his 'friends' but not he girl he loves. Even better, Eugène actually inherits a big sum of money. He who laughs last laughs best!