Under the Sand movie plot

Jean and Marie have been happily married for over 20 years. Their days are leisurely and peaceful. This summer, they came to the country villa for vacation as in previous years. One day, Mary basked in the sun on the beach while Jean went to swim in the sea. But he went and never came back. Mary frantically searched for him, but found nothing. She had to call the beach guards and the police to conduct a thorough search of the beach, but still could not find any traces. With sadness and unresolved confusion, Marie returns to her home in Paris alone. Although she could not face the reality that her husband's life and death were uncertain, she could only endure her grief and threw herself into a dull life. On the surface, it seems that nothing has happened, teaching, fitness, meeting friends, in fact, she has never been able to forget the bits and pieces of being with her husband, and she can't imagine the days without letting go. She is stubbornly convinced that Jean is still alive, and refuses to speak of him in the past tense, as if Jean was living with her. Although she began to try to communicate with Vincent, there was no substantial progress, and her inner desire was difficult to suppress   .