Marc Michel Marrier de Lagatinerie was born in Lausanne, Switzerland on 3 January 1949, the son of Jacqueline Porel (1918–2012), an actress and granddaughter of Gabrielle Réjane, and Gérard Landry, an actor[2][better source needed].
He had three half siblings, one from an affair his mother had with the singer Henri Salvador : his brother Jean-Marie Périer, and two from her marriage to actor François Périer : his brother Jean-Pierre and sister Anne-Marie.
He was married twice, first to French model Bénédicte Lacoste, with whom he had a daughter.
They divorced, and he remarried to Italian actress Barbara Magnolfi.
Porel died in Casablanca on 15 August 1983 of a heroin overdose.