Jerzy Zamiejski is a locksmith in a suburban workshop and an amateur aviator. He builds makeshift planes, he has great ideas to revolutionize aviation, but he lacks the funds to implement them. By chance, she meets Tomasz Kotlica, a Pole who made his fortune in Brazil. He falls in love with his daughter, Janina, but leaves her as a result of an intrigue plotted by Witold. Witold envies Jerzy not only for Janina's favor, but also for his talent in the field of aviation. Thanks to Kotlica's help, Jerzy graduates from the aviation school and the polytechnic. Kotlica urges influential Brazilian Poles to set up a transport company and launch a Poland-Brazil airline. He employs Jerzy as an aircraft designer and constructor. Soon, Jerzy sets off on his first test flight from Warsaw to Rio de Janeiro. On the eve of his departure, Janina visits him and the young people gather again. During the flight, the radio and the entire navigation system break down. The reason turns out to be an oversight by Witold, who also worked on the construction of the plane. The world is convinced of the tragedy - the plane did not arrive on time and probably ran out of fuel. Tormented by remorse, Witold commits suicide. However, Jerzy manages to reach his destination. Polish businessmen in Rio establish a Polish-Brazilian partnership, and Jerzy returns to Janina.