Agatha Christie's The Pale Horse 

Don’t get me wrong, I did like certain elements of this adaptation. But I felt that the book itself outshined the film like the sun outshines the moon. I read almost all of Poirot and Miss Marple before going into the stand-alone novels and short stories. Christie has been the Queen of Crime Fiction longer than Elizabeth II was Queen of England. I have yet to come across her equal. But I was proud of myself when I could figure out the solution and actually get it right. The Pale Horse was, to me, one of her very best mysteries. I could not predict the ending of that one, even though I had come to understand some of her methods of storytelling. It was a true stumper. The answer was brilliant, and simple. But it never occurred to me, and that’s what I like about it.