After her parents get divorced, Marina feels nothing will ever be the same again. The only thing that hasn't changed is that she still spends her summer in the Camargue, the coastal region of France where her grandparents live. But this summer will be truly unforgettable. With Étienne by her side, she regains her hope and finds the courage to start horseriding again, her great passion, and - more important still - manages little by little to banish her sadness, that black worm that is always trying to find a way to reappear. But a serious, unexpected incident means that Marina will have to face up to her own life once again.