Juan, driver of long distance, loves Romina, a teacher of a town through where he drives every day. A morning she requests to him to deliver a small package in a clinic on the town of the province. When Juan is alone, he opens the box and finds a bottle that contains a yellow liquid. Somebody interrupts him. He tenses himself. The bottle falls and breaks. Desperate, Juan obtains another jar; he fills it with his own urine and takes it to the clinic with Romina´s data. When he goes to pick her results up they tell him, she must go personally to the clinic. Romina undertakes the long trip in Juan´s bus. During trip the attraction between them grows. When she arrives to the clinic they inform her that she is diabetic. She must remain in the city to make more examinations and she must also follow a strict diet. Romina very disturbed has dinner with Juan, and he in a romantic and friendly act requests the diet she must do. There he tries to confess the deceit, but he cannot speak. That night they sleep together, but on the following day in the clinic, Romina discovers the truth. She finds out that he always knew that she was not diabetic. She leaves him and he suffers an attack. When he recovers, he decides to return to the town. With some difficulties and much tenderness he manages to recover his relation with Romina.