At the end of the 15th century, a man and a woman, posing as traveling minstrels, are sent by the Devil to a castle to seduce its inhabitants.

Patrica is the wife of Alain de Saulieu, a handsome engineer. She unfortunately loses her husband, who is killed in action during a battle of the First World War. At least, this is only the official truth, for Alain is not dead. Patricia indeed recognizes him one day. But the inverse does not work the other way around: Alain has become amnesiac and he does not remember her. And worst of all, he lives in a conjugal relationship with Germaine, his dedicated nurse, who is now pregnant by him. What has the future in store then for the three (not to say four) of them?