Alain Delon and Romy Schneider had been real life partners from 1958 to 1963, they were no longer a couple when this film was shot, but remained good friends after their split. In 1966, Schneider married director Harry Meyen and had put her career on hold to care for her son David. Alain Delon imposed that Schneider should be his co-star in La Piscine and the film revitalized her career.