 In the 1930s Ricky Masters, an English businessman, marries Madeleine, a fine match socially, but the cultured aesthete is more and more attracted to her sister Dinah, a  Bohemian  painter, and as they spend time together their affair becomes physical, even all the way; yet when she gets pregnant they decide to leave his marriage intact. He raises his son with Madeleine, who tells him only in 1946 that she knew after he had a car accident during a  business trip  to southern France that caused Dinah to loose her unborn daughter; now Ricky wants to leave Madeleine, but she refuses a divorce; after a time in hospital he is told Dinah chose to move back to France without him while she s really living in London, still not the last twist of the drama...