In the summer of 1943, military counterintelligence officer Ilya Titov and his associates managed to accomplish the impossible: prevent an alien army from invading Earth. In this, earthlings were helped by unusual allies - “brothers in mind” from the planet Dosteya. Decades have passed, and now the people of Dostia need help. Their home planet is under the threat of a new enemy. It is impossible to cope with the situation on our own. The Federation makes a difficult decision: to informally ask people for help. General Titov and other front-line soldiers are offered to undergo a unique rejuvenation course and go to Dosteya to join the fight against the invaders there. To do this, they will have to call on all their combat experience to help... The task is difficult. The risk is great. But Titov and his comrades accept the offer...