Tim Allerton stole and switched Linnet's pearls

Tim Allerton’s theft and substitution of Linnet Doyle’s pearls gives Hercule Poirot a second crime to disentangle from Linnet’s murder. Tim had already replaced the genuine necklace with an imitation, and later entered Linnet’s cabin and took the necklace from the bedside table. The genuine pearls were concealed in an elaborately carved rosary in his cabin. His admission establishes the theft, but his visit on the night Linnet died also leaves open a more troubling question: whether he knew she was dead when he took the necklace.

Background and the Earlier Substitution

The theft was not a simple snatching of a valuable necklace after the murder. Poirot’s reconstruction distinguishes an earlier substitution from Tim’s later entry into Linnet’s cabin. The genuine Linnet Doyle’s pearls had been replaced with the Imitation Pearl Necklace before the night of the crime. When the necklace was reported missing after Linnet’s death and then appeared to be returned, Poirot recognized that the returned string was not genuine. The apparent recovery therefore concealed, rather than resolved, the original substitution.

The wider pattern of imitation-jewellery schemes helped direct suspicion toward Tim’s associate, Joanna Southwood. Chief Inspector Japp had reason to suspect that Southwood, who had been associated with a Guild of Modern Jewellery, could have handled jewels, arranged for copies to be made, and worked with another person who carried out the substitution. Poirot also knew that Southwood was an intimate friend of Mrs. Doyle. He inferred that she had sent the imitation necklace to Tim after he came from Majorca on hearing that Mrs. Doyle would be there for her honeymoon. The proposed route was a book with a square cut from its middle pages: Poirot reasoned that such a parcel could pass through the post without being opened. This was his reconstruction, not an admission by Southwood.

The Nighttime Theft

Tim’s own account supplied the immediate circumstances. He had learned that Linnet put the necklace on a small table by her bed. On the night she died, he slipped into her cabin, felt for the necklace, took it, put down another string, and crept out. He said he assumed Linnet was asleep. Poirot established that someone had seen Tim leave her cabin just after one in the morning, making the visit more than a theory and placing it at a consequential point in the murder inquiry.

Tim admitted taking the pearls and accepted that the evidence would lead investigators to them. He explained that the neighboring cabin was only two doors away and that Linnet was occupied by her own troubles, which he believed made her unlikely to notice the change. He also acknowledged that Poirot’s presence aboard the boat had made him uneasy: he was not hardened enough to enjoy sitting beside a successful detective while preparing a risky theft. That anxiety did not stop him. In Tim’s account, the opportunity aboard the boat was unusually favorable, and the exchange had to be attempted sometime.

The Rosary and the Detective’s Deduction

Poirot identified the hiding place as the Rosary Containing the Pearls, which hung in Tim’s cabin. Its beads were intricately carved and unscrewed, though they did not look as if they could be opened. A pearl had been fixed inside each bead with seccotine. Poirot reasoned that Tim had arranged for the rosary to be made specially and had counted on searchers respecting a religious object unless it appeared suspicious. The concealment converted a devotional object into a container designed to evade an ordinary search.

The rosary completed the chain connecting the missing genuine necklace to Tim. Poirot had first considered the sudden disappearance of Linnet Doyle’s pearls in light of the known methods of imitation-jewellery substitution. The fact that the necklace later returned as an imitation changed the meaning of its recovery: the returned string was not proof that the genuine pearls had been restored, but evidence that the substitution had taken place. Tim’s possession of the genuine stones and his admission to entering the cabin confirmed his role in the theft, while leaving the precise handling of every string in the exchange to Poirot’s reconstruction.

Admission and the Unresolved Murder

Tim conceded that Poirot had found the pearls and said they would be discovered where Poirot indicated. He did not, however, implicate Joanna Southwood. He maintained that the way he obtained the imitation necklace was his own business and that the authorities had no evidence against her. Poirot accepted the distinction between Tim’s established theft and the unproved case against his associate. The exchange keeps the limits of the investigation visible: uncovering Tim’s crime did not automatically establish another person’s participation.

The theft’s most serious consequence is its overlap with the murder timeline. Poirot asked whether Linnet was alive or dead when Tim entered. Tim could not say. He remembered the room as very still, but could not recall hearing her breathe; he also could not remember whether the smell of recently fired gunpowder lingered. His answers did not establish what he knew, and Poirot acknowledged that they did not settle the question. Tim insisted that he had not killed Linnet, despite the suspicion created by his presence in her cabin at that hour.

Poirot later used the visit as a possibility to test against the murder evidence, not as proof that Tim was the killer. He considered whether Linnet might have noticed the earlier substitution and threatened to expose it, and whether Tim might have overheard the confrontation between Jacqueline de Bellefort and Simon Doyle before entering the cabin. These possibilities made the theft relevant to the murder’s planning and timing, but the evidence presented did not turn them into a confession or a demonstrated motive. The episode therefore has a double force: it exposes Tim as a pearl thief, while showing how a real crime can become entangled with a larger mystery without resolving it.