It is Christmas Eve. The Lee family reunion is shattered by a deafening crash of furniture, followed by a high-pitched wailing scream. Upstairs, the tyrannical Simeon Lee lies dead in a pool of blood, his throat slashed. But when Hercule Poirot, who is staying in the village with a friend for Christmas, offers to assist, he finds an atmosphere not of mourning but of mutual suspicion. It seems everyone had their own reason to hate the old man.

An urgent cry for help brings Poirot to France. But he arrives too late to save his client, whose brutally stabbed body now lies face downwards in a shallow grave on a golf course. But why is the dead man wearing his son's overcoat? And who was the impassioned love-letter in the pocket for? Before Poirot can answer these questions, the case is turned upside down by the discovery of a second, identically murdered corpse.

Beautiful Caroline Crale was convicted of poisoning her husband, but just like the nursery rhyme, there were five other "little pigs" who could have done it: Philip Blake (the stockbroker), who went to market; Meredith Blake (the amateur herbalist), who stayed at home; Elsa Greer (the three-time divorcee), who had her roast beef; Cecilia Williams (the devoted governess), who had none; and Angela Warren (the disfigured sister), who cried all the way home.

Sixteen years later, Caroline's daughter is determined to prove her mother's innocence.

Framed in the doorway of Poirot's bedroom stood an uninvited guest, coated from head to foot in dust. The man's gaunt face stared for a moment, then he swayed and fell. Who was he? Was he suffering from shock or just exhaustion? Above all, what was the significance of the figure four, scribbled over and over again on a sheet of paper? Poirot finds himself plunged into a world of international intrigue, risking his life to uncover the truth about "Number Four".

Everyone blamed Emily's accident on a rubber ball left on the stairs by her frisky terrier. But the more she thought about her fall, the more convinced she became that one of her relatives was trying to kill her.

The house guests at Styles seemed perfectly pleasant to Captain Hastings. There was his own daughter, Judith; an inoffensive ornithologist called Norton; dashing Mr Allerton; brittle Miss Cole; Doctor Franklin and his fragile wife, Barbara; Nurse Craven; Colonel Luttrell and his charming wife, Daisy; and the charismatic Boyd-Carrington. So Hastings was shocked to learn from Hercule Poirot's declaration that one of them was a five-times murderer.

Gordon Cloade is killed in a London air raid, and his vast fortune passes to his young wife Rosaleen. Five of his relatives are desperate to get their hands on Cloade's money, and Rosaleen begins to fear for her life. The prospects for the Cloades improve when they discover that Rosaleen had a previous husband who perished mysteriously in Africa. Then a mysterious stranger appears in the village, saying that he has something to communicate to her, but the following morning he is found dead.

Beautiful young Elinor Carlisle stands serenely in the dock, accused of the murder of Mary Gerrard, her rival in love. The evidence is damning: only Elinor had the motive, the opportunity, and the means to administer the fatal poison. Yet, inside the hostile courtroom, one man still presumes Elinor is innocent until proven guilty: Hercule Poirot, who is all that stands between Elinor and the gallows.

Nick Buckley was an unusual name for a pretty young woman. But then she had led an unusual life. First, on a treacherous Cornish hillside, the brakes on her car failed. Then, on a coastal path, a falling boulder missed her by inches. Later, an oil painting fell and almost crushed her in bed. Upon discovering a bullet-hole in Nick's sun hat, Hercule Poirot decides the girl needs his protection. At the same time, he begins to unravel the mystery of a murder that hasn't been committed. Yet.

A beautiful heiress has been found dead on a train. A playboy has been stabbed through the heart during a costume ball. An elderly woman suspects that she is being slowly poisoned to death. A prince fears for his reputation when his fiancée is embroiled in another man's murder. A forgotten recluse makes headlines after he is shot in the head. Who but Agatha Christie could concoct such canny crimes? Who but Belgian detective Hercule Poirot could possibly solve them? It's a challenge to be met - in a triumph of detection.