1917. In Petrograd, a young Latvian boy Jezups signs up to work for the revolution and is sent to central Russia to show films and campaign for joining the Red Army. Jezups is a naive idealist and would rather not touch weapons at all, but life destroys his belief that it is possible to do without violence. In the end, Jezups is forced to understand that the ideals of the revolution must be defended not only with a film projector, but also with a machine gun.