The action of the "Dossier Morel" is located in Algiers in 1943 in a half-abandoned winter garden and is transported, by successive backwards, in different places of the Paris of the Occupation. An officer of the secret services questions Lieutenant Jean Morel, aviator of the Free French Forces, who in April 43 crossed the Spanish border to go to Algeria in the French army. But at that time the Germans often sent agents to poison the French forces in Algiers and Morel was accused of being one of them. Is he really a Nazi agent? A clever guy who plays on both sides? An impulsive who has committed imprudences? Or is he totally innocent? The truth breaks out at the end of the interrogation after some rewindings on episodes likely to enlighten the investigation as the activities of Morel in Paris and its clandestine crossing of the Franco-Spanish border.

Inspired by a real event, this story takes place in Germany, before the war where a network of escape works in liaison with the French secret services. A dentist, Dr. Otto belongs to this network. He is worried because he received a strange visit: a French girl, Elisabeth Grenier, niece of the French Consul in Germany, came to beg him to get away from Hans Von Satow, a German anti-Nazi officer. Is Elisabeth sincere or is she an instrument to dismantle the network? In order to find out about it Commander X

Inspired by a real espionage affair of the 1950s, this story takes Commander X to a country beyond the Iron Curtain, while Jacques D., a junior intelligence officer, sent on a mission there, proves to be not be up to the task. Commander X, a friend of Jacques, learns this news by chance and is moved by it. He decides to go there to help Jacques. Will he manage to save it? This episode illustrates a secret service process, the system of the "mailbox" that allows agents

Once again, Commander X opens his files. This story takes place in England during the Second World War. The commander captive in an Oflag manages to escape and to London where he is questioned by the security services. He thinks that after declining his identity he will be released immediately. But for the British, Commander X is just as suspicious as any escaped from occupied Europe and they will conduct their interrogation with subtlety and courtesy not without humor.

Inspired by an authentic espionage case, the "Saint-Mathieu file" is set in its frame, a hotel in Saint-Germain des Prés, some time after the Liberation of Paris. This is the great time of Saint Germain and the hotel became a cabaret 1900. The commander X seeks a former secret agent of the Gestapo who lived in this hotel during the war, next to famous resistance. At the bar, he meets Karin, a singer who once knew this Nazi agent. To allow the investigation to progress, it accepts

Seventh episode of this series which is inspired by authentic facts. Commander X, parachuted from London, is scheduled to complete a mission to Dijon in September 1941. During his contact with a local resistance network, he is charged with a crime and arrested by the French police. This mistake leads him to the Assize Court without his revealing his true identity.

Ce téléfilm se déroule en 1940, dans une petite localité perdue de la forêt amazonienne.Le commandant X, qui se fait passer pour un ethnologue chargé de recherches au musée de l'Homme, traque en Amazonie un ex-officier SS, Brauen qui, sous la couverture de la vente d'émeraudes, tente de reconstituer un réseau nazi. En fait ce Brauen est un personnage fictif. Le vrai chef du réseau est un familier de l'étrange Elga, avec qui le commandant X se livrera à un infernal "jeu de la vérité".

February 1945, in Paris, in Fresnes, in the Pyrenees and in Seville. A man is accused of having delivered to the Germans a woman who wanted to go to Spain and to have stripped her of her jewels. He is condemned to death and must be shot shortly. But he vigorously protests his innocence. Commander X looks after the case and looks for the real killer. Who killed ? Was it the convict's friend who introduced the victim to a smuggler? Is it the smuggler himself? Will Commander X act quickly enough

The action of this tenth and final episode of the series, a hunt for the spy, is located in 1964, in the international fast train "Edelweiss" which goes from Zurich to Amsterdam, with backtracking in a box in Pigalle in 1960, a drawing workshop at FRAM, a tea room on Île Saint Louis, Roger's apartment ... Why did Commander X get on this train? This is probably not for the pleasure of meeting, installed in one of the compartments, one of his old school friends. For twenty years, the commander has seen Roger only twice, in oddly opposite circumstances: the first time, Roger seemed very satisfied but it turned out that his situation was less than brilliant; the second time, on the contrary, he apparently had a comfortable income, but he was visibly worried. From there, to make Roger more than suspicious, there is only one step. But the trip turns out to be hectic. Disturbing characters lurk in the corridors and when the two friends go to celebrate, drink in hand, meet them in the dining car, a mysterious powder is discovered in one of the glasses ... If the commander X s' He is interested in Roger's activities, is it because he suspects him or, on the contrary, because he is trying to protect him? The outcome will provide the key to the enigma of this espionage case triggered by a theft of secret documents at the Air Ministry.