A priest gets a little hot under the collar when the wife he thought was dead unexpectedly returns.

L’Agence O is a famous Parisian private detective firm. Its premises are located in the Passage Choiseul. In front, Torrence leads the shop. In fact, the agency's team is complemented by Émilie le Roux, Mademoiselle Berthe and Barbet, who scrutinize clients through a one-way mirror located behind the desk. Getting hold of a man disguised as an old lady, solving the mystery of the Prisoner of Lagny or discovering who is blackmailing the painter Tigrane Alban does not worry the experts at the O Agency. Les Dossiers de l’Agence O is a French-Canadian television series in thirteen episodes of approximately 55 minutes created by Marc Simenon and broadcast first in Quebec from December 14, 1967 to March 13, 1968 on Télévision de Radio-Canada, then in France from March 11 to June 3, 1968 on the first channel of the ORTF.

Over the course of one night, a gang of twelve criminals carry out a commando-like raid on a small town.

In November of 1939, the British consulate in Norway receives documents saying that the Nazis are conducting secret rocket research in Peenemünde. But the British doubt the authenticity of the so called "Oslo report". Thus, the Germans continue their experiments unimpeded. At the same time, resistance groups from France, England, Poland, and Germany try to find and to sabotage the secret Nazi research base. When the first "V 2" rocket is successfully launched, the Allied commanders finally become interested in the "Oslo report".