Olivier Suarez is married and a father while working as is a chemical engineer in Paris. Each week for several months now, he has been travelling by night train to Barcelona for work. One evening, while dining alone at the restaurant wagon, Olivier stumbles across Elisa's eyes, an attractive and brilliant lawyer who also divides her time between Paris and the Catalan capital. Olivier is both intrigued and captivated by the young woman's extreme nervousness. Over the weeks, travel after travel, their conversation will become more personal and intense. Soon a passionate idyll will be born between them.