Ariadne Oliver's friend Mark hears about the murder of a priest who had a list of names tucked into his shoe. He had written down the list after hearing a deathbed confession, and was promptly murdered in the street only moments later. Mark goes to Ariadne for advice as he becomes more and more deeply involved in this mystery. He hears rumors about a place called The Pale Horse, where witches and mediums call on dark forces. But surely that is all nonsense, and no one could believe that witchcraft would really kill a person with a mere thought.

This mystery has a very creepy atmosphere, since Mark gets weirded out by the witchcraft and begins to wonder what connection there could be with the murder of the priest. He can't tell what is real and true anymore, and starts to think that maybe these witches are really calling on spirits or something. But his rational mind tells him that it must be all fake and there has to be a scientific explanation for what is happening.

I love how chaotic Ariadne Oliver is. She's so scatter-brained in the way she talks, because her mind is running a million miles a minute, but if you can follow her train of thought, it makes perfect sense. She's the one who has the flash of brilliance that gives Mark the final clue to solve the mystery and save the day!

The writing really emphasizes the creepiness of the Pale Horse and the people involved. The eerie mood pervades every aspect of the story and gradually infects each character as they get more and more involved. At the start, they scoff at the idea of witchcraft, but then they start to wonder and they get confused. But it's all illusion and suggestion and ambience.

Mark meets a young lady, Ginger, who can help him to uncover certain facts, and together they follow a line of inquiry that puts them both in danger. Ginger proves herself to be up to the challenge, but Mark is worried for her safety. The romance between them is quick but intense because there is so much as stake. I really enjoyed seeing them get closer as they investigate together.

The plot kept me guessing right up to the end, and I had no idea who the murderer could be. Agatha Christie always surprises me!