The Girl with the Golden Eyes (1961)

La Fille aux yeux d'or

A skirt-chasing fashion photographer meets a charming young woman who captures his interest immediately. She is not wholly forthcoming, but after a period of time, he realizes that he is in love with her -- she is not just another conquest. It takes awhile before he also realizes that she is the partner of his femme associate who is possessive, at the very least.