The Beguines.

Hélène, a fragile and romantic teenager, discovers that her father, a rich business man, has a mistress. Curious, she decides to go and meet this woman who is described as strange. At the first chance she has she goes to her house in the Ramparts of Béguines... from then on she goes back often, discovering a new world of artists and nightowls where she also experiences love in the arms of Tamara.