Cardinal Richelieu (Christopher Logue) and his power-hungry entourage seek to take control of seventeenth-century France, but need to destroy Father Grandier (Oliver Reed - The Brood ) - the priest who runs the fortified town that prevents them from exerting total control. So they seek to destroy him by setting him up as a warlock in control of a devil-possessed nunnery, the mother superior of which is sexually obsessed by him. A mad witch-hunter is brought in to gather evidence against the priest, ready for the big trial.
The Devils is a 1971 British historical drama horror film directed by Ken Russell and starring Oliver Reed and Vanessa Redgrave. Russell's screenplay is based partly on the 1952 book The Devils of Loudun by Aldous Huxley, and partly on the 1960 play The Devils by John Whiting, also based on Huxley's book.