All over the world there are wars that claim the lives of thousands of children every year. On the fragments of a once united country, children act as ambassadors of peace, called upon to correct the mistakes of adults. An ordinary Moscow schoolboy, imbued with the horror of war, sends a letter to an unfamiliar peer in Lugansk. Thanks to this act, the whole class comes from the bombed-out city for the holidays to Moscow. Will the guys be able to find a common language or has the war irrevocably divided the children's worlds?