A young woman finds herself imprisoned in a lavish room within a vast stately home, which later turns out to be New Carfax Abbey. Despite the desperate efforts of a search party to locate her, she tragically hangs herself from the staircase.
In present-day New York City, we meet Evelyn "Evie" Jackson, a struggling artist who makes ends meet by freelancing for a catering company alongside her best friend, Grace. After the death of her mother, Evie takes a DNA test, leading her to discover a distant cousin in England named Oliver Alexander. Upon meeting Oliver, he shares a scandalous tale about her great-grandmother, Emmaline, who bore a secret child with a black footman — a revelation that shakes Evie's world.
Invited to a family wedding in England, Evie travels to Whitby, where she arrives at the impressive New Carfax Abbey. Here, she is introduced to the lord of the manor, Walter De Ville, along with Mrs. Swift, a longtime maid, and his loyal butler, Mr. Field. During her visit, she also encounters the rest of the Alexander family and the maids of honor, the amiable Lucy and the haughty Viktoria.
As Evie's time at the Abbey progresses, she finds herself drawn to Walter, with a growing mutual attraction. However, the atmosphere takes a dark turn as multiple housemaids mysteriously disappear under Mr. Field's watch, seemingly victims of an unseen terror. One night, Evie is startled by a ghostly apparition in her bedroom. The following day, she sneaks into Walter's office, uncovering his research on her prior to her arrival. Although initially furious, Evie and Walter reconcile, culminating in a passionate night together.
During a rehearsal dinner, Evie anticipates meeting the wedding couple but is shocked when Walter announces their engagement instead. In a horrifying twist, Mr. Field brutally slits a maid's throat and serves the blood to Walter, Lucy, and Viktoria, who are unveiled as vampires. Walter reveals that Evie's ancestors, the Alexanders, have historically offered a woman from their lineage to him in exchange for protection and wealth. He explains the tragic fate of Emmaline, who had killed herself after remorsefully ending the lives of innocents and losing her love, Evie's great-grandfather, along with their infant son. The Alexander family has struggled to find their next sacrificial female until they located Evie.
Imprisoned in the cellar, Evie has a chilling encounter with Lucy and Viktoria. Viktoria confesses to being the apparition she saw and shows her Dee, a maid who vanished days before. After being trapped in a coffin by Viktoria, Evie is rescued by Mrs. Swift, a friend of Emmaline.
Hiding in a shed, Evie uncovers the bodies of the maids and the lifeless form of Mrs. Swift, slaughtered by Mr. Field. Desperate, she escapes into town and seeks help from an elderly couple, who reveal themselves as Jonathan and Mina Harker, working for De Ville. They knock Evie unconscious, and she awakens to find herself in the presence of De Ville, who is feeding on a maid and ultimately reveals himself to be Dracula.
Faced with an ultimatum, Evie is compelled to wed De Ville, while Dee is bound nearby to be sacrificed at the altar. At the climax of their vows, Evie bites De Ville's arm, consuming his blood and becoming a vampire herself. In a burst of power, she ignites the chapel in flames, stabs him in the heart, rapidly aging him before escaping with Dee. Just as freedom seems near, Viktoria ambushes them, but Lucy intervenes, leading to a ferocious battle that results in both Lucy and Viktoria turning to ashes as they impale themselves on a spear.
Evie's struggle is not over; she finds herself confronted by Mr. Field but manages to overpower and kill him. The final showdown with De Ville sees him grasping her throat until she severs his wrist, kicking him into the flames and ensuring his demise. Although Evie loses her newfound powers as a result, she escapes just as the manor is consumed by fire.
Two weeks later in London, Evie and Grace hunt down Oliver, who is about to flee after paying off the police. The two women have one intention: to enact vengeance upon him for deceiving Evie and for his role in the vampire-related murders.
