Heart of a Dog

A weary stray dog is lured into the professor's large Moscow apartment with a piece of sausage. The dog, named Sharik, is taken in and cared for by the maids while living among the professor's medical practice. He remains curious about why he was brought there.

The professor implants the pituitary gland and the testicles of a recently deceased alcoholic and petty criminal, Klim Chugunkin, into Sharik. The operation takes place in the professor's medical space within the apartment. Soon after, Sharik begins to show signs of changing and taking on new traits.

In the days following the transplant, Sharik begins to take on human traits and language. He inherits the donor's bad manners, aggression, profanity, and drinking, while also adopting the bizarre name Poligraf Poligrafovich Sharikov. Despite his humanity, he remains prone to cat hatred.

Sharikov secures a job at the Moscow department for extermination of stray animals. He adapts quickly to his new role and begins to see the world through a bureaucratic lens. His work ties him to the city's new Bolshevist structures.

Sharikov associates himself with the new Bolshevist building administration, which seeks to strip part of Professor Preobrazhensky's apartment. This bureaucratic move adds pressure on the professor and heightens the conflict over living space. The alliance marks a darker turn in his behavior.

Sharikov's presence disrupts life at the apartment as he steals money, breaks furniture, and floods the place during a cat chase. The professor and Bormental try to manage repeated chaos that follows his misbehavior. The living space becomes increasingly uninhabitable.

Preobrazhensky and his assistant Bormental observe that all attempts to reform Sharikov fail. They confront the limits of science and surgery when his criminal tendencies persist. The situation worsens as Sharikov refuses to change.

Sharikov attempts to denounce the professor to the Soviet secret police. This signals a dangerous loyalty to the regime and threatens the doctor's safety. Preobrazhensky becomes aware of the scheme and the looming danger.

Sharikov refuses to leave the apartment, and a violent confrontation ensues when Bormental attacks him. Preobrazhensky then decides to reverse the procedure, hoping to restore order. The reversal marks a turning point in the story.

The procedure is reversed and Sharikov reverts to a dog. He remembers little of the events, and is content to live in the professor's apartment again. The doctor and Bormental reflect on the limits of their experiment.

Sharik, as a dog, is left living in Preobrazhensky's apartment without further changes. He accepts his fate and the quiet after the chaotic days. The film ends with him coexisting in the same household.