Hammer Films’ horror masterpiece Dracula is to be rereleased in UK cinemas in October, including footage believed to have been lost for more than six decades after it was deemed too gruesome for audiences.

The 1958 movie starring Christopher Lee as Count Dracula and Peter Cushing as Doctor Van Helsing has been fully restored in 4K.

The restoration reinstates footage previously seen only by audiences at the film’s original Japanese theatrical release in 1958.

The recovered material, which was discovered in a Warner Bros warehouse, has never been released before in the UK or US and has never appeared on home entertainment in any territory.

The chief executive of Hammer Films, John Gore, called it “the recovery of a piece of British film history that audiences believed had been lost for ever”.

Speaking to Deadline, he explained that censors and distributors had cut the footage after audiences fainted during screenings when Lee’s vampire lunged at the neck of his victims, his fangs dripping with blood. “It was the fangs that scared them,” he said. “People were screaming, which was the point.”

The film changed the landscape of horror cinema, with a famous scene of Lee looming at the top of a dark staircase and declaring: “I am Dracula”.

His performance redefined the on-screen vampire for generations, introducing the bloodshot eyes, predatory fangs and visceral physicality, while Cushing delivered what is widely regarded as the definitive screen portrayal of Van Helsing, a fearless, intelligent vampire hunter.

“Think of every Halloween and you see all those fangs – that’s a Hammer and Christopher Lee invention,” Gore said. “It all started when Christopher Lee said ‘I want more teeth with this’, so they came up with something that had some bite.”

Gore said Bela Lugosi had no fangs when he played Dracula in Tod Browning’s 1931 film, and the count in FW Murnau’s 1922 classic Nosferatu “was like a rabbit”, with no bite at all.

The producer wanted to find ways to honour Hammer’s horror legacy after taking control of the company less than three years ago. “Hammer’s business was based on the censor,” he said. “Getting that X-rated certificate was crucial to marketing, but they could only go so far because the censors didn’t like what they saw, all that blood.

“Warner Brothers have this massive storage near LAX [Los Angeles international airport] where everything from the 1920s onwards is there. There’s like 10 Batmobiles and god knows what. And they found the director’s cut of the original 1958 Dracula.”

Other reintroduced footage “is a bit that’s so famous”, Gore continued. “It’s where Christopher Lee descends on the woman and is about to bite her. It’s so sexual and they had to trim that because it just looked like it was nothing to do with vampires.

“So they had to trim a bit of the sexual stuff and then how he’s destroyed at the end. They cut quite a lot out because they went: ‘It’s too gruesome’ … All the crucial points that were axed are now back in.”

Dracula was the second on-screen pairing of Lee and Cushing after they starred in the 1957 film The Curse of Frankenstein. They went on to become one of the most celebrated rivalries in cinema history.

The announcement of the restoration and rerelease was made on World Dracula Day, 26 May, the same date as Cushing’s birthday. Lee’s birthday was 27 May.

The film will also be made available on home entertainment.