A co-production between the British Abacus Productions and the American-based Cannon Group, the film was shot in England in 1969 under the title The Velvet House.

Walter Eastwood is a wealthy and controlling patriarch who demeans and abuses his diminutive artist wife, Edith, and their teenage daughter, Jane.

During dinner at the family's large estate one night, Walter's friend, Gregson, arrives, and is greeted by Jane at the door.

When Walter plans a hunting trip to his remote cottage, Edith and Jane opt to remain home, while Rupert is unable to accompany him owing to a prior obligation.

Edith and Jane arm themselves with a shotgun and trail Walter to the cottage, but their plans to kill him are thwarted when he hears them enter the house.

Using a funnel, Edith forces more liquor down Walter's throat as he lies incapacitated, before she and Jane drag his body upstairs and place it in his bed, in an attempt to make his death appear as an alcohol-narcotic overdose.

While Edith prepares tea, a suspicious Reid investigates the home, finding the bottle of sleeping pills in Walter's room.

After Reid departs, the women drive the box containing Walter's corpse to a remote abandoned factory and push it over an embankment into a pond.

At the table, Walter humiliates Jane by reading a letter she has received from Benjy Smith, a local boy who is infatuated with her.

The script, written by Olaf Pooley, was originally titled The Velvet House and was loosely based on the film Les Diaboliques (1955).

[3] The low budget meant that expenses had to be minimal, so an actual house was used for on-location filming, with the remainder shot at Merton Park Studios in London.

Howard Simpson of The New York Times attended the opening night of Cauldron of Blood and Crucible of Horror and writes in his review that the former is 'painful to watch' and that 'the one to see, without running' is the latter.

He states that Crucible of Horror is 'superbly directed by Viktors Ritelis and beautifully played by Yvonne Mitchell, Sharon Gurney and Michael Gough' and notes that 'for tight, merciless tension and venom, the movie is uncommonly effective and engrossing'.

The anonymous review says that 'Director Viktor Ritelis livened the pace with fast-cut flashbacks, psychedelic dream sequences and some well-mounted horror touches at the end'.

It notes the high quality of the acting and reports that 'Young Sharon Gurney gets introductory billing, celebrating the occasion by plunging in with a nude scene, hysterics and a sharp sense of defying her elders'.

[17] Ann Guarino of The New York Daily News gave a middling review, awarding the film two stars out of four and cited its "deadly pace," adding that it "will barely keep you awake.

As MGM had assumed The Cannon Group catalog after Crédit Lyonnais took full control from Pathé Communications, MGM/UA Home Video put out an officially licensed release in 1993 and reissued in 1998, using a transfer made from an original film element with the US title.