Juan and Pilar (Giménez Cacho and Toussaint) return to Mexico City on the same train. Destiny cross their paths in a taxi stop, off the train station. A taxi cab arrives and they take each other's baggage by mistake. After that, they spend two days looking for each other, trying to recover their stuff. In the meantime, Juan reads Pilar's diary and she listens to his thoughts recorded on tape. Love begins to grow between these two proper strangers.