The story is about a brave boy who never takes off his hat.

Romka Marchenko, a young kid who is participating in movie shooting tries to stop international spy.

1918. After the death of the mother, the father decides to take the children to Moscow to see a distant relative. On the way, the guys experience a raid by a White Guard gang on a train, the death of their father, and meet the homeless child Yashka, who brings a plan to Lenin - how to destroy all the bourgeoisie and all the counter-propaganda in one day. The boys become involved in revolutionary events, and ahead is Moscow, a chance meeting and conversation with Lenin and Dzerzhinsky, the fight against counter-revolution...