So This Is Paris (1926)

Georgette lives in Paris with her unexciting, effeminate husband, an actor and interpretive dancer. Meanwhile, Suzanne lives across the street and reads romance novels while dreaming of someone more exciting than her own lackluster spouse Maurice. Each woman happens across the other's husband and begins her dream affair. Four people, each cheating on their spouse, and none of them is aware that their own spouse is cheating. Who will find out first, and how?