Pete Walker’s grimy women in prison films is one of his best, a gleefully sadistic exploitation piece that outraged some quarters of the critical establishment of the day, a fact that would have delighted a director whose main raison d’etre seemed to have been rattling as many cages as he could find. It was his first collaboration with screenwriter David McGillivray (who turns up a couple of times in the film, uncredited, as Caven) and actor Sheila Keith, a winning combination that would help him make the best films of his career.

House of Whipcord starts with a much-discussed opening caption that reads “this film is dedicated to those who are disturbed by today’s lax moral codes and who eagerly await the return of corporal and capital punishment…” The caption is said to have been added to the film by Walker after the BBFC passed the film with only one minor sound effect cut (the removal of a whiplash) and after board Secretary Stephen Murphy identified the film’s two antagonists as send-ups of moral campaigners Lord Longford and Mary Whitehouse. What follows was just the sort of the film that would have given the clean-up campaigners a fit had they actually watched it.

At the height of a storm, a terrified young woman flees for her life, finding help from a truck driver, Jack Kind (Ivor Salter). In flashback, we learn that the woman is French model Anne-Marie DeVerney (Scottish model Penny Irving affecting a terrible accent) who leaves her photographer boyfriend at a party when she finds that he’s showing off a shot of her being arrested by the police for public nudity. She finds herself attracted to fellow partygoer Mark E. DeSade (Robert Tayman, Count Mitterhouse from Hammer’s Vampire Circus (1972)), who whisks her off to his remote country estate to get away from it all. But DeSade is procuring young women for his deranged parents, ex-reform school matron Margaret (Barbara Markham) and her blind lover Justice Bailey (Patrick Barr) who run a private prison where they mete out punishment to “morally corrupt” young women. Anne-Marie is imprisoned and witness at first hand the humiliation, brutalisation and eventual execution of her fellow inmates while her flatmate Julia (Ann Michelle) and Julia’s boyfriend Tony (Ray Brooks) search for her.

Given Walker’s later admiration for Whitehouse and her work, it’s hard to know if we’re meant to simply dismiss that opening caption as a satirical barb or take it at face value. The clash between Walker’s more traditional British politics and the liberally minded McGillivray may explain the film’s seemingly effortless ability to find something that could potentially offend everyone. The film itself is, in part at least, about the stand-off between the generations, a recurrent theme in horror from the late 1960s to the mid-1970s. It pitches the staid, reactionary and politically conservative older generation and the far more carefree and progressive (sexually, socially, politically) younger crowd in a vicious, sadistic battle of ideologies, a war that no-one was ever going to win.

House of Whipcord is an almost relentlessly grim and even depressing film, though there are flashes of the bleakest humour here and there. The aged, blind and retired judge Justice Bailey is named for the Central Criminal Court of England and Wales in London, colloquially known as the Old Bailey – atop which sits a blindfolded statue of Lady Justice, her lack of vision supposedly representing the impartiality of the law. Other names are less subtle – Mark E. DeSade and Mr Kind in particular are a bit on the nose for a film as determinedly downbeat as House of Whipcord, a film which pulls the late shock reveal that Anne-Marie has been hanged by the couple even as her friends close in on the prison. Though in fairness, McGillivray’s own uncredited character mocks DeSade’s name too, as though the writer knew full well that it was utterly absurd.

Apart from Irving (who later turned up barely contained in her sexy outfits as Young Mr Grace’s first secretary in the BBC sitcom Are You Being Served? (1972-1985)) whose performance is frankly awful the film boasts a first-rate cast. Markham is great as the devious and manipulative Wakehurst, Dorothy Gordon is almost as menacing as one of her underlings, Barr almost gets out sympathy as the duped Bailey, unaware that his young prisoners are actually being murdered and Tayman gets to use his own voice here, something denied him in his Hammer film. But the show is well and truly stolen by the remarkable Keith who spits out McGillivray’s venomous dialogue with unrestrained malevolence (“I’m going to make you ashamed of your body, DeVerney. I’ll see to it personally”). It’s a magnificent and genuinely terrifying performance, the first of several for Walker, though the subsequent Frightmare (1974) would be her most chilling.

House of Whipcord was made before Walker became a more polished director, before his rough edges were filed off and his genre films became less interesting (Schizo (1976), The Comeback (1978), House of the Long Shadows (1983)) and is all the better for it. There’s a rawness to House of Whipcord, a savagery missing from his later films. He and his regular cinematographer Peter Jessop make excellent use of the real Littledean Jail in the Forest of Dean in Gloucestershire, now a crime museum with an exhibit on House of Whipcord that seems to think that it’s a Hammer film (because every horror film made in Britain during the 70s must have been a Hammer film…)

UK distributors Miracle wanted to retitle the film Whiplash Girls which makes it sound even more like a softcore porn film than House of Whipcord. Imagine some poor punter already lured to the film by vague promises of S&M titillation, only to find that, although there’s some gratuitous nudity, this is actually one of the least titillating British horrors of the 1970s. Pity too, the foolhardy British viewer who ventured along to their local fleapit expecting something akin to television’s Within These Walls (1974-1978), an altogether more staid series about a women’s prison, albeit a legitimate one this time, that had begun on ITV in January 1974, just three months before Walker’s film was released.

Frightmare, with its tale of cannibalism and madness in the English countryside, may be the more visceral film, but House of Whipcord retains its power to shock and disturb even now. It stands apart from anything else being made in British cinema in 1974 (apart from the equally brutal and sadistic Frightmare) and is a terrific showcase for Walker at his most unsettling and unrestrained.