After a tragic event, Lucia moves to an isolated island where she tries to grasp the circumstances that brought her there. In Madrid, she works as a waitress. One day after work, she goes to the apartment owned by her boyfriend Lorenzo. He is a writer and suffers from depression. There she finds his farewell note and news from the police. Six years earlier, Lorenzo had had a passionate affair with an unknown woman that resulted in the birth of his daughter Luna. Lorenzo only found out about his daughter much later…