Based on

Movies like My Step Brother Frankenstein (2004)

One day Pavel, a young man wounded in the war, suddenly shows up at the home of a Moscow scientist name Krymov and claims to be his illegitimate son. Krymov denies this, but out of compassion he helps arrange a necessary operation for Pavel. Then certain things begin happening which suggest to Krymov that he may have a psychologically unstable fellow on his hands.