The fifth-grader Borya, a fidget and an inventor, was appointed a counselor in the first class. Not taking this at first seriously, the boy gradually became interested in new and unexpected duties for him.

Four inseparable friends — Sergei, Nina, Oska and Zhenya — spent all their school childhood on the Clean Ponds, in Moscow. But the school is over, and in their beloved gazebo they dream of the future, swear fidelity to each other and do not yet know that tomorrow war will break out and they will become participants in terrible events.