Ventajas de viajar en tren

After arriving home to find her husband completely crazy, young literary editor Helga Pato (Pilar Castro) is forced to put him into a psychiatric clinic in the north of the country. On the return train journey, a stranger, Ángel Sanagustín (Ernesto Alterio), a psychiatrist investigating a notorious case, strikes up a conversation with her. He shares tales of his patient, Martín Urales de Úbeda (Luis Tosar), whose story unfolds as Helga's own life is revealed, including her abusive relationship with Emilio (Quim Gutiérrez).