Forbidden (a.k.a. Scarlet Heaven ) is a 1949 British thriller film, produced and directed by George King, and starring Douglass Montgomery, Hazel Court and Patricia Burke.^[3] King's last production both as independent producer and as director, it also features the final screen appearance by Montgomery.

In Blackpool, trained chemist Jim Harding has been reduced to making a living peddling potions and medicines from a fairground stall with a former army colleague Dan Collins.

Trapped in a loveless marriage with the vulgar, shrewish and domineering harpy, Diana, a woman who harbours ambitions of breaking into showbusiness, Jim finds himself attracted to the kinder working-class Jane Thompson, who sells candyfloss and ice cream at an adjacent stall. Jim does not reveal to Jane that he is married as the two fall in love and begin an affair. Diana meanwhile is engaged in a liaison of her own with the older Jerry Burns who, she believes, will be able to help with her theatrical aspirations.

Diana finds out about Jim's affair and visits Jane at home. Diana reveals Jim's married status, tries to convince Jane that Jim is a serial philanderer and that she is only the latest in a succession of young women he has targeted, and offers her cash to end the relationship. Jane refuses to be bought off and confronts Jim, who protests that he is caught in an intolerably unhappy marital situation with a selfish, unscrupulous woman. Jim then confronts Diana and demands a divorce, which she refuses out of hand.

In desperation, Jim determines that the only solution is to kill Diana. Aware of her addiction to multiple medications, he uses his knowledge to concoct pills containing a lethal dose which he slips amongst her habitual supply. Then, having second thoughts, he hurries home but finds Diana dead. In a panic, he buries her body beneath the floorboards in his workshop, only to discover later when clearing up in the bedroom that the deadly pills he made up are untouched – Diana, in fact, has died of natural causes and his disposal of her body has been unnecessary and incriminating.

Diana's disappearance in unexplained circumstances arouses the suspicions of the police, who come to the conclusion that all the indications are that she has been murdered by her husband. Jim attempts to flee but is tracked down and chased through the streets of the town, where the final confrontation takes place at Blackpool Tower.

• Douglass Montgomery as Jim Harding
• Hazel Court as Jane Thompson
• Patricia Burke as Diana Harding
• Garry Marsh as Jerry Burns
• Ronald Shiner as Dan Collins
• Kenneth Griffith as Johnny
• Eliot Makeham as Pop Thompson
• Frederick Leister as Dr. Franklin
• Richard Bird as Jennings
• Michael Medwin as Cabby
• Andrew Cruickshank as Inspector Baxter
• Peggy Ann Clifford as Millie
• Peter Jones as Pete
• Erik Chitty as Schofield
• Sam Kydd as Joe

As of 30 June 1949 the film earned £64,400 in the UK of which £50,680 went to the producer.^[1]