The Pale Horse is a mystery novel written by acclaimed author Agatha Christie and first published in the United Kingdom in 1961. It tells the tale of a man named Mark Easterbrook and his investigation into a mysterious agency operating out of an old pub, once dubbed the Pale Horse, and the agency’s role in several unexplained deaths.

Plot Summary

Mark Easterbrook, a local historian, is sitting in a café when two young women begin fighting, and one of them tears a handful of hair out of the other’s scalp. A week later, Mark sees the death notice of the young woman who’d been depilated in the morning obituaries. During the same period, a local priest is murdered and found with a list of names, all of whom, the reader soon discovers, are dead. One woman died in the presence of the priest that very evening, and the only witness to the murder is a pharmacist, Mr. Osborne, who was closing his shop when the crime happened. Detective-Inspector Lejeune investigates the cases.

Mark Easterbrook, meanwhile, attends a performance of Macbeth with his date Hermia Redcliffe. After the performance, they go to dinner and run into friends David and Poppy. The foursome discuss the existence and power of witches, inspired by the witches in the play they had just seen. Poppy mentions an establishment in a nearby village called the Pale Horse that seems to dabble in the subject, but she won’t say more. The next day when Mark visits Poppy’s place of employment, she refuses to speak about the topic, visibly afraid even to mention the Pale Horse.

Mark’s cousin Rhoda, however, does have information about the Pale Horse. She tells him that three women, Thyrza Grey, Sybil Stanfordis, and Bella (their cook) live in the old inn and are infamous for their participation in magic, witchcraft, and spiritualism. One afternoon Mark, Rhoda, and a small group of friends have lunch at the home of a wealthy collector, Mr. Venables, and then visit the Pale Horse as a local tourist attraction. In meeting Thyrza and the other women, Mark becomes even more intrigued.

Then, while visiting a pub after his stop at the Pale Horse, Mark comes across a visitor’s book that contains names he recognizes: names that appeared on the list carried by the deceased priest days earlier. Believing there is a connection between the recent deaths and the strange residents of the Pale Horse, Mark decides to investigate, a fact that he shares with the wife of the local vicar, Mrs. Calthrop.

Meanwhile, Inspector Lejeune discovers that the suspect witnessed by Mr. Osborne, the pharmacist, could not have been the priest’s murderer since the man had been identified and was found to be bound to a wheelchair and thus could not have been seen walking past the store window. Mark, for his part, forms an alliance with a woman named Ginger whom he met at a Church festival days before. Ginger proves to be enthusiastic and resourceful, and the pair hatch a plan to discover more information.

Ginger meets with Poppy and presses her for more information, while Mark determines to interview the mother of the girl who had died from the café. Ginger finds out that a man named Bradley will get her closer to the mysterious events associated with the Pale Horse. And Mark is more certain than ever of the truth of his suspicions when he meets the dead girl’s mother and she blanches and shakes at the mention of the Pale Horse. Once Mark and Ginger meet again, they make a plan to visit Bradley. Mark will pose as a client who wishes to have his wife killed, with Ginger posing as the victim-to-be. They inform Inspector Lejeune of their plan to have an ally in the police force.

Mark meets with Bradley to negotiate a price. He then participates in a ritualistic performance at the Pale Horse led by Thyrza and her companions as they try to convince Mark of the reality of their powers. Eventually, Mark discovers Poppy has more information to share, and he solves the mystery of the deaths: no witchcraft or supernatural means have been employed. The victims have been poisoned with thallium, one side effect being rapid hair loss.

Having discovered how the murders were committed, Lejeune is able to then unmask the retired pharmacist—not Mr. Venables, who had been the prime suspect to that point—as the mastermind behind the crimes. Osborne had lied about witnessing Venables outside his shop and had committed the crimes to profit by the scheme. Once the crimes are solved and the mystery wrapped up, Mark realizes that he is in love with Ginger and proposes to her.