Hallowe'en Party recap

At a children's Halloween party, thirteen-year-old Joyce Reynolds boasts that she once saw a murder. She is later found drowned in the apple-bobbing tub, and Ariadne Oliver brings Poirot to Woodleigh Common. He reviews several local deaths and the disappearance of Olga Seminoff, companion to wealthy Mrs Llewellyn-Smythe, after a codicil in Olga's favour was denounced as forged. Joyce had actually copied a story told by Miranda Butler, the true witness. Rowena Drake killed Joyce because she believed the boast, then killed Joyce's brother Leopold when he blackmailed her. Rowena and her lover, landscape designer Michael Garfield, were also responsible for removing Olga and concealing her body in the elaborate garden; Olga's claim to the inheritance was genuine. Michael tries to kill Miranda at the quarry after realising what she saw, but Poirot and the police save her. Judith Butler reveals that Michael is Miranda's father. The murders are exposed, Olga's remains are recovered, and Miranda survives the attempt to silence her.

Ariadne Oliver is visiting Judith Butler in Woodleigh Common when she helps prepare a children's Halloween party at Rowena Drake's house. The busy gathering includes games, costumes, and an apple-bobbing tub. During the preparations, thirteen-year-old Joyce Reynolds hears Mrs Oliver discussing crime and boasts that she once witnessed a murder without realising at the time what she had seen. The adults dismiss the claim because Joyce is known to invent stories for attention. After the party, however, Joyce is missing. She is found drowned in the tub, held beneath the water after the other guests had moved away.

Mrs Oliver asks Poirot to investigate whether Joyce's boast caused her death. He consults retired Superintendent Spence, who knows the district, and begins interviewing the household, teachers, children, and neighbours. Joyce's unreliability makes the central question difficult: the killer may have acted on a true statement, on a misunderstood event, or simply on the fear that the girl knew too much. Miss Emlyn helps Poirot assess the children without assuming they observe and remember like adults. Rowena Drake describes the party's movements, while Joyce's younger brother Leopold watches the inquiry with an interest in information and reward.

Poirot reviews unresolved events from the years in which Joyce might have seen something. The most significant cluster surrounds the wealthy Mrs Llewellyn-Smythe, the elaborate garden she commissioned from landscape designer Michael Garfield, and her foreign companion Olga Seminoff. A codicil apparently left money to Olga, but it was challenged as a forgery; Olga then vanished under suspicion. Other local deaths and scandals offer alternative meanings for Joyce's claim. Poirot visits the ornamental landscape and senses that its beauty has encouraged people to treat it as an artistic world apart from ordinary moral rules.

The investigation separates what Joyce said from what she could actually have observed. Her habit of borrowing other children's experiences suggests that the boast may contain a real event but the wrong witness. Judith Butler's daughter Miranda is imaginative, quiet, and closely attuned to Michael Garfield's garden, making her memories important even though she has not advertised them. Poirot also questions the assumption that Olga forged the codicil: if it was genuine, her disappearance benefited those who otherwise would have lost control of Mrs Llewellyn-Smythe's property. Leopold's unexplained access to money indicates that another child has noticed an adult secret and is trying to profit from it.

Leopold is found dead after attempting to turn his knowledge into blackmail, confirming that the danger extends beyond Joyce's original claim. Poirot concludes that Joyce repeated a story first told by Miranda and that the murderer silenced the wrong witness, then acted again when Leopold became troublesome. The disputed will, Olga's disappearance, and the physical design of the garden now form one line of inquiry. Searchers focus on places where a body could have been incorporated into a landscape without disturbing its intended appearance. At the same time, Miranda becomes the person most at risk because she can supply the memory that Joyce merely borrowed.

Poirot identifies Rowena Drake as Joyce's killer. Joyce had repeated Miranda Butler's account of witnessing an earlier crime, but Rowena believed Joyce herself knew the secret and drowned her in the apple-bobbing tub. Leopold observed enough to blackmail Rowena, and she killed him as well. The older crimes join Rowena to her lover, Michael Garfield. Olga Seminoff's codicil was genuine, and her removal allowed control of Mrs Llewellyn-Smythe's money and Garfield's costly garden to remain elsewhere; Olga's body is found concealed in the ornamental grounds. When Michael understands that Miranda is the true witness, he tries to kill her at the quarry, but Poirot and the police prevent it. Judith Butler reveals that Michael is Miranda's father, though he is still willing to sacrifice her to preserve the life and artistic dream built with Rowena. Miranda survives, and the linked murders and inheritance deception are exposed.

Poirot discovers that Joyce did not personally witness the old murder she boasted about. She had borrowed a story told by Miranda Butler, the true witness, and repeated it to impress Ariadne Oliver. Rowena Drake nevertheless believed Joyce knew the secret and drowned her in the apple-bobbing tub. Joyce's brother Leopold later used what he had noticed to blackmail Rowena, so she killed him as well. The older conspiracy links Rowena with landscape designer Michael Garfield, her lover, and with the disappearance and death of Olga Seminoff. Olga's disputed inheritance from Mrs Llewellyn-Smythe was genuine; removing her allowed the estate and the garden financed from it to remain under the conspirators' control. Olga's remains are found concealed in the ornamental grounds. Michael recognises that Miranda, not Joyce, is the dangerous witness and tries to kill her at the quarry, but Poirot and the police intervene. Judith reveals that Michael is Miranda's father, making his willingness to sacrifice the girl still more decisive. Rowena and Michael's scheme collapses, and Miranda survives.