Hearing about the revolution in the hospital, the sailor Gulyavin goes to Petrograd, and from there with a detachment of Ukrainian volunteers he is sent to Ukraine. The troop is joined by cavalrymen under the command of the anarchist Lelka. The chief of staff, Stroyev, reproaches Gulyavin with negligence - you cannot take an untested detachment. However, the desperate courage of Lelka in battle with the White Guards gives Gulyavin not only respect for her, but love...

Dr. Fiedler, in a secret underground laboratory located in the reserve, is working on experiments to create bestial creatures endowed with human intelligence. It would seem that contact with the beasts on an equal footing took place, but devoid of human morality and compassion, beast-like creatures rebelled against their creators. The journalist Battley, who learns about the monstrous rumors from the reserve, decides to conduct his own investigation and goes to the wilderness, where he encounters the products of Fiedler's terrible experiences.