The Murder at World’s End (2026) is a historical locked-room mystery by Ross Montgomery and the first installment of the Stockingham & Pike series. Set in Cornwall, England, during the global panic surrounding the 1910 passage of Halley’s Comet, the novel follows Stephen Pike, a young man recently released from a juvenile detention facility. After being hired under mysterious circumstances at the isolated estate of Tithe Hall, Stephen finds himself a prime suspect in the murder of his employer, the eccentric Viscount Stockingham-Welt, who is found dead inside his sealed study with a crossbow bolt in his eye. To clear his name, Stephen must team up with the Viscount’s sharp-witted, foul-mouthed great-aunt, Miss Decima Stockingham, to uncover the truth. The novel explores themes of Class and Reputation as a Mask for Corruption, Reframing Social Invisibility as a Source of Power, and The Manipulation of Truth Through Competing Narratives.

The Murder at World’s End is the adult debut from Ross Montgomery, an award-winning British author previously known for his acclaimed work in children’s literature. Several of his books for young readers, including Alex, the Dog, and the Unopenable Door (2013) and The Midnight Guardians (2020), have been shortlisted for the Costa Children’s Book of the Year award, and his 2024 novel, I Am Rebel, won the Waterstones Children’s Book of the Year. In The Murder at World’s End, Montgomery draws on the historical context of the Edwardian era, particularly the rigid upstairs/downstairs social hierarchy and the real-world hysteria caused by the comet, to create an atmospheric and complex mystery that pays homage to Golden Age detective fiction.

This guide refers to the 2026 William Morrow first US edition.

Content Warning: The source text and this guide feature depictions of cursing, class discrimination, graphic violence, substance use, addiction, death, and death by suicide.

Plot Summary

Set in May 1910, during worldwide panic over the arrival of Halley’s Comet, the story follows Stephen Pike, a young man recently released from a Borstal Institution (a juvenile detention facility) after serving two years for grievous bodily harm. Stephen arrives at Tithe Hall, a grand manor on World’s End, a tidal island off the coast of Cornwall, carrying a letter signed by Lettice Welt, one of the Viscount’s cousins, asking Head Butler Mr. Stokes to hire him discreetly as one of her charitable endeavors. Mr. Stokes agrees partly because the household is in dire need of someone capable of managing Miss Decima, the Viscount’s sharp-tongued elderly aunt confined to the decrepit Nursery wing.

The Viscount, Lord Conrad Stockingham-Welt, gathers the household and announces his belief that the comet’s poisonous gases will destroy all life on Earth. He orders the staff to seal all the rooms in the East Wing and lock everyone in their rooms overnight. His guests include his cousins: Edwin Welt, a Member of Parliament who expects to inherit the estate after the Viscount’s death, Rear Admiral Jolyon Welt, Lettice Welt and her young grandson Gilbert, and the Viscount’s colleague, Professor Wolff Müller, a German scientist. Edwin reacts to the Viscount’s announcement with rage, having expected a discussion about the will rather than a doomsday scheme.

As the staff seals the house, Stephen works alongside Lowen, the antagonistic first footman who views him as a rival. He briefly encounters Lettice, who makes it clear she has no idea who he is despite signing his letter of recommendation. Later, Stephen is taken to the nursery to see Miss Decima, who reveals that she arranged his hiring by forging Lettice’s handwriting, wanting a servant willing to break rules so she could observe the comet outdoors. She insists Stephen wheel her outside in her bath chair. They spend hours watching the comet while Stephen transcribes her readings and observations. She tells him of her bitter history: Once a brilliant scientific mind, she sacrificed her career to care for her father, and the Viscount later stole and published her research as his own.

The next morning, Stephen notices blood seeping out from under the door to the Viscount’s study. He and Lowen break down the sealed door and find the room is pitch-dark. Lowen switches on the light, revealing the Viscount slumped dead in his chair with a crossbow bolt buried in his eye, taken from a suit of armor in the hallway. Mr. Stokes arrives behind Temperance, a maid Stephen befriended the previous day, and drops the breakfast tray. The smashing teapot nags at Stephen for days.

Edwin assumes control of the household, placing the island in lockdown until the police arrive and the Viscount’s will is read. The housekeeper reveals that Lawrence Welt, the Viscount’s father, died 20 years earlier in an identical manner, shot through the eye with a crossbow. Lowen publicly suggests that Stephen, as the only newcomer and the one to discover the blood, is the obvious suspect. At dinner, Edwin raises the possibility that Miss Decima, attended only by Stephen on the night of the murder, could be responsible.

Miss Decima summons Stephen and proposes they solve the murder using scientific reasoning, arguing that his criminal past will inevitably place the blame on him unless they find the real killer. When Inspector Jarvis of Scotland Yard arrives, he proves theatrical and incompetent, first accusing Stephen and then Miss Decima with insubstantial evidence and faulty reasoning. Miss Decima produces the notebook of comet observations as evidence of Stephen’s whereabouts at the time of the murder. Mr. Stokes makes Stephen swear his innocence on the Bible and promises to conceal his criminal past from the police.

Stephen recruits Temperance as an investigative partner. An avid reader of detective novels, she proposes that the Viscount was killed by a mechanism hidden in the sealed study that deployed the crossbow. Miss Decima grudgingly accepts her as an ally, and the three form an investigative team. They search the study but find no mechanism. Miss Decima assigns Stephen to watch the suspects and Temperance to investigate Lettice, who is secretly blackmailing Professor Müller for an unspecified reason. Stephen eavesdrops on Edwin’s frantic phone call with a solicitor’s clerk and learns the Viscount changed his will a week before his death.

The investigation advances on multiple fronts. Temperance impersonates Edwin on the telephone and learns the Viscount was accompanied by an unrecognized man when he changed his will. When Jarvis publicly accuses Mr. Stokes of masterminding the murder using Stephen as a hired killer, Miss Decima dismantles the theory: The study door was sealed with wax and locked from the inside, making Jarvis’s scenario impossible. Lowen is demoted after Stephen traces missing cellar wine taken by Lowen to bottles hidden under Jolyon’s bed, and Lowen vows revenge.

Miss Decima eliminates Lettice and Müller from suspicion after Stephen uncovers that the nature of Lettice’s blackmail is unrelated to the crime. At Sunday dinner, Miss Decima provokes the family by mentioning an old scandal that causes Edwin to freeze. The team develops a glass-plate photograph Müller had taken of the study into a cyanotype (a sun-exposed photographic blueprint) and compares it to the crime-scene sketch, but the images appear identical. Stephen discovers a hidden target-practice site near a waterfall, with trees painted with eye-shaped targets scarred by arrow strikes, proving the murder was planned by a long-term resident rather than a recently arrived guest.

Inspector Jarvis is found dead, struck by a fallen marble bust, and a sudden storm traps everyone on the island. Stephen finally identifies the critical change in the study: A butler’s mirror above the fireplace was present on Wednesday but missing on Thursday. Müller had removed it for his photograph to avoid glare, which is why neither image showed it. Later, the mirror was permanently removed so no one would see the killer’s reflection in the dark room.

That night, the power goes out. Temperance lures Stephen to the waterfall, where he finds Lowen’s body. She strikes Stephen with a hammer, binds him, fills his pockets with stones, and pushes him into the swollen river. She reveals herself as the Viscount’s illegitimate daughter, raised in poverty by her ruined mother Elsie, a former ladies’ maid dismissed after her affair with the Viscount was discovered. She planned the murder as revenge and mentions an accomplice at the house targeting Miss Decima.

Stephen frees himself from the river and races back to find Mr. Stokes holding a crossbow on Miss Decima, who bluffs with a tea caddy she claims contains explosives. The full truth emerges: Lawrence Welt’s death was an accident caused by Mr. Stokes’s drunken father misfiring the crossbow during a hunt. The Viscount witnessed it and used the secret to control the Stokes family for 20 years. Temperance found out the truth of her parentage from her mother’s letters, applied at Tithe Hall, and recruited Mr. Stokes as her accomplice.

Stephen explains the locked-room murder: Mr. Stokes stayed in the study overnight while Temperance climbed to the roof and fired the crossbow down the chimney as Mr. Stokes lured the Viscount to the fireplace. Mr. Stokes then sealed the chimney, removed the mirror, and stood silently in the dark until the door was broken down the next morning, slipping out behind Temperance when the lights came on. The cold tea from the smashed teapot, made the night before, was the clue that had nagged at Stephen all along.

Stephen, at Miss Decima’s nod, lets him go. Miss Decima offers Temperance the opportunity to leave quietly in exchange for Stephen’s safety. Temperance accepts and vanishes. At the will reading, the Viscount’s estate passes to Miss Decima, who takes immediate command. A newspaper article reveals Mr. Stokes wrote a full confession before dying by suicide. Temperance was never found. Miss Decima invites Stephen to London, where she plans to establish a detective agency and fund scientific scholarships for young women. Stephen accepts. The novel closes with the comet continuing its orbit, set to return in 2061.