It is difficult for Kapka Butyrev: his father is at the front, his mother died during the first Nazi raids, Kapka, like many of his friends, works at a factory, and his two sisters run the house. It is also difficult for the cabin boys transferred to the Volga from besieged Leningrad. The fascists here too do not allow them to calmly comprehend marine science. But what can I say! It’s difficult for everyone: war... But it’s still easier when you unite together against the enemy. And the Three Great Masters help in this fight - Amalgam, Isobar and Drone Garden Head. Before the reader is a surprisingly bright and life-affirming story, full of faith in Victory, by L. Kassil, written in 1944. For middle school age.