Armando Andreoli is a dapper but elderly engineer, traveling to a conference in Bologna. He is annoyed by the young, glamorous blonde who invades his train compartment and even more annoyed when she seems to have followed him to the conference. But when his hotel reservation falls through, he agrees to share her room. The night passes without incident, but her fiance, coming in the next morning, doesn't see it like that and dumps her. Soon, the relationship between the two evolves into real romance and Armando takes a new lease on life.