Heart of a Dog

In Moscow during the winter of 1924, a stray dog is foraging through trash and is scalded with boiling water by a cook. A renowned surgeon, Filipp Filippovich Preobrazhensky, arrives and offers the dog a piece of sausage. The grateful animal follows him back to his flat, where he is named Sharik.

Sharik settles into the professor’s flat and meets Bormenthal and the two female servants, Bunina and Ivanova. Despite the professor's anti-communist views, his treatment of Bolshevik leadership keeps him untouchable on the housing committee. Sharik quickly adapts to life as a pampered gentleman’s dog in a busy Moscow household.

After a few days, the professor reveals his true intention to use Sharik in a radical medical experiment. He locks Sharik in the bathroom as preparations for the operation begin. The dog senses the looming transformation as the lab is readied.

In the laboratory, Filipp Preobrazhensky trepans Sharik’s skull and implants a human pituitary gland. His torso is opened for grafting human testicles taken from Klim Grigoryevich Chugunkin. The procedure is perilous and only adrenaline injections prevent the dog from dying on the table.

Weeks after the operation, Sharik begins transforming into an unkempt, rudimentary human, and is issued papers under the name Poligraf Poligrafovich Sharikov. He chooses the publishing-related name, while the calendar-based preference is ignored. The narrative shifts to Bormenthal’s case notes, chronicling the astonishing change.

Sharikov resists learned etiquette and mocks manners as relics of Tsarism, insisting that it is better to behave naturally. He refuses to shave, dresses in unwashed clothes, and eats like a slob. The professor and Bormenthal watch as their experiment unsettles the household.

Sharikov’s presence escalates tensions when he turns on a bathroom spigot while chasing a cat, flooding the apartment. The locked door traps everyone inside as the water pours in. The domestic order collapses under his unrestrained behavior.

Sharikov attempts to sexually assault one of the female servants, prompting Bormenthal to beat him and force apologies. Enraged, Sharikov leaves the apartment and disappears for several days.

Bormenthal begs the professor for permission to dose and kill Sharikov with arsenic, but the professor insists on not slandering the dog. He explains that the human body parts used in the operation cause the defects, and wonders whether repeating the procedure with a genius would help the human race. He ultimately refuses to undo the operation or to allow murder.

Sharikov begins working for the Soviet government, spending his days catching stray cats. He returns home with a female coworker, presenting her as his common-law wife. The odd domestic arrangement further unsettles the household.

The coworker is told that Sharikov is the product of a lab experiment rather than a heroic man from Siberia. She leaves the apartment in tears, horrified by the truth. The professor’s and Bormenthal’s attempts to manage Sharikov’s new life only deepen the tensions.

The following day, Pyotr Alexandrovich, a senior party official and friend of the Professor, arrives to inform him that Sharikov has denounced Preobrazhensky to the Cheka. He notes that government distrust makes them relatively safe for now. When Sharikov returns to the flat, the professor and Bormenthal order him to leave for good.

With a search warrant, the police arrive alongside Schwonder and demand Sharikov. The professor proclaims the change as a natural phenomenon, while Bormenthal summons Sharikov. The creature returns to dog form as the police depart with their case unresolved.

In the ending, Sharik hints that the professor plans to bring home a human brain and remove the pituitary gland again, implying a continuation of experimentation or lingering memories of his time as a human. The implication is that the project may resume or be repeated. The story closes with science and humanity still at odds.