House of Whipcord is a 1974 British women-in-prison thriller film directed and produced by Pete Walker and starring Barbara Markham, Patrick Barr, Ray Brooks, Ann Michelle, Sheila Keith, Dorothy Gordon, Robert Tayman and Penny Irving. The film was Walker's first collaboration with screenwriter David McGillivray, who went on to write a further three films for him. It also marked the horror film debut of actress Sheila Keith, who went on to star in four more films for Walker.

The film opens during a night-time thunderstorm when a frightened, confused and disheveled young woman, Anne-Marie, runs down a country road and is picked up by a trucker. We see through flashbacks how the young woman came to be in such a situation.

While at a gathering in a London art gallery, naive French model Anne-Marie DeVernet is shocked to see that her photographer boyfriend is exhibiting a recently shot photo where she is seen being arrested by the police for public nudity. Humiliated, Anne-Marie dumps the photographer but soon finds solace in enigmatic fellow partygoer Mark E. DeSade, who offers to take her to his isolated country estate to escape the scandal her now ex-boyfriend has caused her.

Unfortunately, Anne-Marie soon discovers that Mark is a procurer of young girls for 'moral correction' by his sadistic mother, ex-reform school matron Margaret. Years earlier, Margaret had been brought to trial when her corrupt reign over a girl's reform school led to the suicide of a young French girl under her charge (although in truth, Margaret murdered the girl and made it look like a suicide).

Found not guilty but dismissed from her job in disgrace, she seduced the High Court Judge who presided over her case. The judge, previously critical of the 'permissive society' of England of the 1960s and 70s, then left his wife for Margaret, who bore him a son (Mark) who worked with her to turn their mansion home into a secret illegal prison for 'morally corrupt' and 'delinquent' young women, complete with a group of tough female wardens who administer a harsh regime of corporal punishment upon their prisoners. However, the now retired, blind and senile judge is oblivious to the fact that Margaret is in fact using the prison to torture and punish these young women, who are also sanctioned with 'demerits' during their incarceration, such that strike one is solitary confinement for two weeks, strike two is 40 lashes, and strike three is death by hanging.

Anne-Marie soon falls foul of Margaret's cruelty as she reminds her of the girl she had previously killed and whose death cost her her career and reputation. Meanwhile, Anne-Marie's concerned flatmate Julia and Julia's boyfriend Tony track down Mark, who has now discovered the full extent of his mother's murderous deeds at the prison after seeing her minions dispose of a prisoner's corpse.

Anne-Marie makes multiple escape attempts, but is recaptured every time. Her friends eventually find the prison, but too late to save her. She has been hanged after earning a third 'demerit'. As the police arrive outside, Mark confronts his mother and is mistakenly killed by her. Margaret then hangs herself. The judge and his wife's henchwomen are arrested, and Julia and the other surviving prisoners are freed.

The film was shot on location in London and the Forest of Dean, Gloucestershire, England during the summer of 1973. The prison in the film was Littledean Jail, in the village of Littledean, Gloucestershire.