One evening in 1942, when many parisians fled from the Germans to the Cote d'Azur, movie director Marc Allégret went to see Minou Philip tell the fortune by drawing cards in the Hotel du Parc where Marc Philip was manager at that time. Minou was utterly dedicated to helping her son with his career, but at the same time was worried that the intense life of an actor would be too much for a ponderous child like Gérard. Marc Allegret was therefore ready to tell Gérard he is not suitable for an actor if he would not show enough talent. He chose a scene for Gérard to recite, from Jacques Deval's étienne, a scene where étienne wants to run away and become a writer, against his father's will. Gérard was stunning and Allégret could do but one thing, help the young boy move on with his acting career.
One of Allégret's friends was leading an acting course in Nice, which was where Gégé was sent. He was very studious and when his father was not around, he and Minou would rehearse the given texts. Allégret also did all he could to find the perfect movie role for Gérard. He did find it eventually, that of the young Phil in Blé en herbe by Colette, which role expected all the fragility, innocence and violence Gérard had in him, but alas the movie never got to the big screen. Gérard was disappointed; nevertheless he went to the Victorine studios daily. It was incomprehensible for many that after breathtakingly reciting the monologue of Fantasio of Les Cadets de l'Ocean he did not get the role in that movie either.
Eventually he was to be seventeen-year old Mick in André Roussin's comedy, Une Grande Fille toute Simple. Gérard is silent throughout the play, and gets to speak his mind only in the last scene, where he talks bitterly about adolescent love to people who think they know what love is. Those who saw the play were astounded at Gérard's talent and said that he possessed all there was to possess in acting from the moment he stepped on the stage. Gérard was exactly the right age for his part, and his youthful emotions shook the audience. The play was a big success from the very first day.
The next step in his career was playing the main role in André Haguet's Une Jeune Fille Savait, and according to his partner, Svetlana Pitoeff, "Gérard's exceptional character was immediately acknowledged by the whole world". Every evening Gérard would try to embark on yet another metaphysical journey to find new facets to his character. Working with this play was not easy, considering uncomfortable trains and dirty hotel rooms, but Svetlana Pitoeff describes Gérard as a light-hearted person, who always put a smile on the others' faces with his jokes.
Almost at the same time Yves Allégret cast him in La Boite aux Reves. This was to be Gérard's first movie role, about which there is not much information. In it, he was one figure among the many. Gérard was impatient for bigger roles, and because the theatres of Paris had reopened, Minou and her two sons decided to move to the capital.