She got her first major break when she met French director Louis Malle. He cast her in his movies "L'ascenceur pour l'échafaud" (1957) and "Les amants" (1958), which established her as a movie star in France. She also appeared in Roger Vadim's "Les liaisons dangereuses" (1959) and Peter Brooks's "Moderato cantabile" (1960), but it is with François Truffaut's iconic movie "Jules et Jim" (1961) that she became an international star.