Élise lives alone in an apartment on the Breton coast. One day, in an isolated creek where she is used to swimming, she discovers the body of a drowned woman. This tragic event plunges her into a melancholic state. Who was this woman? What are the exact causes of her death? She still has no answers to her questions when her son, Damien, a pupil at high school in Paris, comes to spend a few days with her.