It is 1880 and a rich Englishman with a terminal disease, Reginald Longstaff, meets a young and beautiful American called Diane at a Normandy beach. He falls in love with her but he doesn't dare speak to her. However, Agathe, Diane's companion, gets her to come and see him on his death bed where he asks her, as a last favour, to marry him. She refuses. Two years later, at the basilica of Vézelay, Agathe thinks she sees a healthy Longstaff and tells Diane about the eerie meeting. Could it be a look-alike? A relative? A ghost?