This feels like a response from Ealing Studios to the success of the Gainsborough melodramas, though it is set among the Victorian commercial class, rather than the aristocracy. Googie Withers is the brassy, mercenary wife of an alcoholic publican who she poisons to promote her greater sexual freedom, and to take over the business.
She gets strychnine by sexually manipulating an inexperienced teenager (Gordon Jackson), who is seeking to squirm from under the heel of his oppressive father (Mervyn Johns), who owns a pharmacy. The story is set in Brighton, but the accents of his large, but tight knit family come from all over the UK!
It is Robert Hamer's debut as director, and he conspicuously spotlights the ambient cruelty of the period; the rigid parenting, the absence of law, the primacy of class and ignorance. Which is the context for a spectacular performance from Googie Withers as a stupid but imperious egotist, the squalid consequence of a libertarian society.
In a chilling subplot, the pharmacist experiments by pitilessly starving guinea pigs which his sweet natured daughter buys cabbages to feed. Maybe informed by rumours from Germany at the end of the war? It's a leisurely but atmospheric murder story set in the shadows of gaslight, which gets lost in the deep psychological darkness of its villains.