Marc was born in Basle. He was the son of André Gide's former tutor, and met Gide in 1918, when Marc was fifteeen-year-old and André forty-nine. Gide at once fell in love with the boy, who was brilliant and handsome. In order to win the esteem and affection of the boy, Gide wrote for him a novel, Les Faux Monnayeurs (The Money Forgers). Thus, between the middle aged man and the boy started a "long and joyful friendship". Gide, with his friendship, that soon became love, gave to Allégret an impulse for his own creative work. In July 1925 Marc Allégret accompanied his lover Gide in a journey to the Congo where they remained for two years. Gide was very jealous of his young lover.

Marc Allégret became a gifted film producer. Documentary film maker at firs, he passed to the subject-films, as Le Lac aux Dames (The Ladies Lake, 1934), Les beaux jours (The Beautiful Days, 1935), Orage (The Storm, 1937), Entrée des artistes (Actors' Door, 1938), who were shoot in France; and Blanche Fury (1947), shoot in England.

Marc Allégret (left) and André Gide (right)