After France fell to Germany in June 1940, Mouly became a civilian again, and earned a living working odd jobs. Mouly befriended an artist named Bernard la Fourcade, and the two established a studio in Auteuil.
After France was occupied by Germany in June 1940, Mouly resumed his life as a non-combatant and earned a living through freelance work. Mouly became acquainted with an artist named Bernard la Fourcade, and the two collaborated on artistic projects in Auteuil.