In a small town in the interior of São Paulo, everyone lives happily: Tinoco and his fiancée Joana, Pirulito and Nhá Barbina. One day, the men in charge of opening a railroad arrive and, with them, trouble. Paulo, one of the engineers, tries to get Joana away from Tinoco. Tinoco is accused of stealing the workers' money and is arrested. Tonico pressures the delegate to investigate the case so that Tinoco can prove his innocence.