As the sun sets in 1974, a solitary Secret Service agent experiences a harrowing escape from a sinister English estate where unholy rites are being conducted under the scrutiny of the enigmatic Chin Yang. In his final breath, he divulges to his superiors the existence of a malevolent cult comprising four influential individuals: a government minister, a peer, a general, and a well-known scientist. The agent's camera had documented their faces, but amidst the revelations, an unsettling fifth photograph emerges, showing an empty doorway that raises doubts regarding its validity. To shield the implicated minister, Colonel Mathews, a veteran of the Secret Service, discreetly contacts Inspector Murray from Scotland Yard and enlists him for an independent investigation. Insightfully, Murray suggests enlisting the expertise of Professor Lorrimer Van Helsing, a distinguished scholar in the realm of the occult.
The cult's dark forces soon strike, abducting Jane, the Secret Service secretary, leading her down a path influenced by Count Dracula's insidious curse. Murray sets out with Secret Service agent Torrence and Jessica, the granddaughter of Van Helsing, to confront the threat at the estate. The trio splits up: Murray and Torrence delve into the interior to confront Chin Yang, while Jessica ventures into the depths of the cellar seeking clues. Amidst her search, Jessica discovers Jane, transformed into a vampire and tragically chained to a wall. The disturbance awakens other captive female vampires, who turn their attention toward Jessica. With urgency, the agents rush to Jessica's defense, barely escaping the ensuing chaos.
In the heat of the moment, Murray ultimately drives a stake through Jane’s heart, ensuring the safety of his team before fleeing the estate alongside Torrence and Jessica. Little do they know, Van Helsing has made an urgent visit to his scientist acquaintance, Julian Keeley, one of the conspirators, at his lab. Keeley, grappling with mental instability, is clandestinely developing a project aimed at producing a dangerously contagious strain of the bubonic plague. Van Helsing’s arrival coincides with Keeley’s presence among the suspects, leading to a conversation that is abruptly interrupted when Keeley’s guard shoots Van Helsing, rendering him unconscious. Upon regaining awareness, Van Helsing is horrified to find Keeley's lifeless body hanging, and the destructive plague bacillus has mysteriously vanished.
As the 23rd of the month approaches, unease blankets Keeley (played by William Franklyn), with his cryptic research notes guiding the astute Professor Abraham Van Helsing](/actor/peter-cushing) toward the curious property developer D.D. Denham. The professor's analytical prowess uncovers the ominous truth—Denham is indeed the resurrected Dracula himself. The realization incites Van Helsing to race to Denham's stronghold, constructed upon the sacred grounds where the Count had previously met his demise. There, he confronts Denham and attempts to end the vampire with a silver bullet, only to be thwarted by Dracula's shrewd henchmen.
As the stakes escalate, Jessica, Murray, Mathews, and Torrence find themselves under a fierce assault while surveilling the foreboding country house. Tragedy strikes as snipers unleash terror, claiming the lives of Torrence and Mathews. Murray and Jessica are taken captive, becoming pawns in Chin Yang’s malevolent plot. In a moment of daring, Murray cleverly eludes his captors and confronts Yang in the cellar, dispatching her with a decisive blow from a mallet, while the other female vampires meet their end as Murray utilizes the purifying power of running water from the fire sprinkler system.
In a dark twist, Dracula, accompanied by his devoted minions, arrives at the country house. With chilling intent, he reveals his plan to make Jessica his consort, positioning her as a critical element in his scheme to unleash a catastrophic plague upon humanity. Amid growing dissent among his minions, Dracula's iron grip keeps their voices silenced. He commands John Porter to shatter a vial, releasing the deadly bacteria and putting the unsuspecting minister at risk. Just as panic ensues, Murray prevails over a guard in the computer room, igniting an explosion that triggers a fire and breaks open the ritual chamber.
Amid the ensuing chaos, two uninfected conspirators seize an opportunity to escape as Murray heroically rescues Jessica. The minister, now infected, succumbs to the inferno. Dracula engages in a brutal confrontation with Van Helsing, yet the savvy professor outsmarts the Count, leading him into a trap and impaling him through the heart with a fence post. As Dracula disintegrates into ashes, Van Helsing claims the ring that once embodied Dracula's malignant power, heralding the conclusion of a dark chapter in the fight against evil.
