Career
Malagnac was also a businessman and art collector. Malagnac met Peyrefitte on the set, from when they started a long association professionally and personally. This formed the background to Peyrefitte"s novel, Notre Amour (Éd Flammarion, 1967) and to L"Enfant de cœur, (an allusion to Malagnacs role as a choirboy (Enfant de Choeur) in the film).
At the age of sixteen Malagnac became Peyrefitte"s secretary.
As a young man he was eventually adopted by a childless aristocratic lady, last of her lineage, called d"Argens de Villèle, and was allowed to join her name to his. Contrary to what was sometimes said, Malagnac was not adopted as the son of Peyrefitte.
He was at one time his universal heir, but it is not sure that this lasted until Peyrefitte"s death. As an adult, Malagnac"s career (often financed by Peyrefitte) included the ownership of Le Bronx, one of the first openly gay night-clubs in Paris, the import of United States king crab, and briefly the management of French singer Sylvie Vartan, a disastrous undertaking which almost bankrupted Peyrefitte, who was forced to sell artworks and erotic antiquities to pay the resulting debts.
Their marriage lasted until his death.
On December 16, 2000, Malagnac was killed by smoke in a fire at his recently bought farmhouse in Saint-Étienne-du-Grèson He died just six weeks after Peyrefitte.