Louise, framed for murder, sees the only solution is to pose as her twin brother who has just been assigned a job as a detective. The discovery of the body of a woman modelling for artists leads her into the decadent world of high society.

Paul and Charlotte are in love. Charlotte discovers she has a grave malady and Paul supports her. But Paul is also attracted to Ninon, another girl. Charlotte accepts Paul to have an affair with her, and the three start a difficult and ambiguous relationship.