Endless Night is one of the very best books that Agatha Christie wrote in the last fifteen years of her life. I think it's under-rated, perhaps because it re-uses one of her earlier ideas for a plot twist. But it does so in a very pleasing way. Not an easy book to adapt for the big screen, though, and the 1972 film version is not, I think, widely admired.
But when I saw it as a student, I enjoyed it, and when I watched it again the other night, I enjoyed it all over again. This was the last film directed by Sidney Gilliat, a talented director whose previous work included the film of Green for Danger, and a writing credit for The Lady Vanishes. He does a fairly good job of handling the plot twists, though of necessity he has to make various changes to the story structure. One or two scenes are a little clumsy, but overall I think it works.
Gilliat had the benefit of an excellent cast. Hywel Bennett, who plays Mike Rogers, a drifter who marries a rich woman, is excellent. At around this time, Bennett was a bankable actor. He was charismatic, and very good at playing ambivalent characters. He'd have been superb as one of Ruth Rendell's amiable sociopaths - what a shame this never happened. And he was very good as the homicidal doctor in the 70s TV version of Malice Aforethought.
Two contrastingly beautiful women, Hayley Mills and Britt Ekland, play crucial roles in the story, while George Sanders is suitably suave as the family lawyer, and Peter Bowles plays the likeable cad with his customary gusto. This is an eerie mystery, about an apparent curse, a magnificent house, and a diabolical murder scheme, and it all makes for good entertainment.