'Nightmare' (1964) – Freddie Francis.

Stylish director, and hugely beloved Hammer Films icon Freddie Francis's darkly circuitous chiller has an especially gripping screamplay by fellow lauded Hammer alumnus Jimmy Sangster, in this instance taking a most diabolical inspiration from Clouzot's deadly cool thriller 'Les Diaboliques'. A highly strung student suffers debilitating night terrors of such severity she must return to the rather austere, Gothic-inclined family home wherein the much younger Janet (Jennie Linden) experienced a grievous trauma so devastating that her frequent nightmares seem so distressingly vivid she becomes wholly convinced that these foul, lurid visions of ever-encroaching horror might not be mere fear-flocked figments of her increasingly fractured psyche, but something far more corporeal in nature, whereby it is not only her already tenuous hold on reality that is threatened by these grimly intrusive apparitions, Janet is in desperate fear of her very life! With its sublimely creepy chiaroscuro lighting, remarkably crisp and efficient direction by maestro Freddie Francis, a sinuously sinister script by Sangster, and a heartfelt, emotionally engaging performance by Jennie Linden as the horribly tormented Janet, 'Nightmare' is no less of a profoundly macabre, monochrome masterpiece than 'The Haunting', or Bryan Forbes's 'The Whisperers', this Hammer Films B/W classic is a sinister masterclass in grimly atmospheric, slowly simmering, psychologically dense, sweat-soaked shock! The visual quality of the wonderful Second Sight Blu-ray is outstanding, and includes some worthwhile extras, 'Nightmare' comes highly recommended.