 Betty Farnwell, a rich widow living in Nice, decides to marry Philippe, a good-looking but self-interested man. No sooner has he got married than he meets bewitching young Eve, Betty s niece, and falls for her. Eve becomes his lover but the trouble is that she happens to be as calculating as he is. As a result she plans to marry a rich young man as Philippe is bound by the ties of marriage. Philippe can t stand such a prospect and decides, with the complicity of the young woman, to murder Betty...