In 1838, real estate agent Thomas Hutter is tasked by his eccentric employer, Knock, with traveling to the Carpathian Mountains to finalize a property purchase for a nobleman named Count Orlok. Thomas leaves behind his fragile wife, Ellen, who is plagued by recurring nightmares and somnambulism, warning that an ancient force is tracking her soul. Ellen is left under the care of close friends Friedrich and Anna Harding.

Upon arriving in Transylvania, locals warn Thomas away, treating Orlok's castle as cursed ground. Thomas ignores their warnings and enters the decaying stronghold. He meets Count Orlok, a gaunt, bald monster dressed in aristocratic rags. During their contract signing, Thomas accidentally cuts his thumb; Orlok’s predatory thirst breaks through his polite facade. Orlok catches sight of Ellen’s portrait miniature, becomes consumed with desire, and signs the purchase of a property directly across from Hutter’s home in Wisborg.

Over subsequent nights, Thomas is imprisoned in the castle, subjected to feeding and psychic drain. Concurrently in Wisborg, Ellen falls into feverish trances, experiencing the same supernatural assaults as her husband across the continent. Thomas discovers Orlok sleeping inside an earth-filled coffin and realizes he is trapped with a vampire.

Orlok departs for Germany aboard the schooner Demeter, hiding in crates filled with plagued soil and swarms of rats. One by one, the crew is killed or driven mad by the phantom on board. Back in Wisborg, Knock loses his mind, eating vermin and worshipping his master’s imminent arrival from inside an insane asylum.

The ghost ship crashes into Wisborg harbor with the entire crew dead. Orlok slips ashore unseen, releasing thousands of black rats that quickly spread the Black Death across the town. Thomas, having escaped the castle, desperately races home on horseback, collapsing upon his arrival. Dr. Sievers and occult scholar Professor von Franz identify the crisis not as natural illness, but as the vampiric curse of the Nosferatu.

Learning from ancient texts that only a sinless woman can destroy the fiend by willingly giving her blood until the rooster crows, Ellen realizes her destiny. She lures Orlok into her bedroom at midnight. As Orlok feeds, entranced by her sacrifice, he loses track of time. The morning sun breaks through the window, engulfing Orlok in daylight and dissolving him into ash, though Ellen succumbs to her wounds just as Thomas enters the room.

The climax flips traditional monster encounters into a psychological and spiritual sacrifice. Ellen Hutter recognizes that the vampire cannot be defeated with bullets, knives, or physical confrontation. Her lifelong connection to Orlok was not random; she served as his spiritual beacon, and only by weaponizing that obsession could the town be saved.

By willingly holding Orlok in her embrace until daybreak, Ellen strips him of his predatory control. The sunrise burning Orlok demonstrates that daylight and pure self-sacrifice shatter the supernatural plague. Ellen dies not as a helpless victim, but as the deliberate savior of the city, leaving Thomas to mourn the cost of ignorance and hubris.