The Peculiar Kleptomania Outbreak
Mrs. Hubbard, the warden of a student hostel called Hickory Road, asks Hercule Poirot about a series of strange thefts and vandalism among her residents. Poirot initially dismisses these as petty crimes, but he becomes interested in the illogical list of stolen items: a stethoscope, flannel trousers, a box of chocolates, a cut rucksack, and a diamond ring found in soup. He senses a darker purpose than simple student pranks. The atmosphere at the hostel is tense, with students showing fear rather than just annoyance, suggesting the thefts are a cover or a distraction from something more serious.
Poirot's Investigation Begins
Poirot, with Miss Lemon, begins his investigation at Hickory Road. He interviews the residents, a diverse group of international students including Nigel Chapman, Sally Finch, Colin McNabb, and Akibombo. He quickly notices their individual habits, goals, and hidden worries. The students are generally unhelpful and secretive, each seemingly hiding something. Poirot focuses on the random nature of the stolen items, believing them to be clues in a larger, still unknown, puzzle. He also notes the general mess and lack of order within the hostel, which Mrs. Hubbard struggles to manage.
The First Murder: Celia Austin
The seemingly harmless thefts quickly escalate when Celia Austin, a resident, is found dead in her bed from a morphine overdose. Her death first appears to be a suicide, but Poirot immediately suspects murder. Celia had admitted to some of the earlier petty thefts, saying they were a cry for attention. Her death confirms Poirot's belief that the thefts were a smokescreen. The diamond ring, one of the stolen items later returned, becomes important, as it belonged to Celia, who had reported it stolen.
The Nursery Rhyme Connection
As Poirot examines the seemingly random items, he suddenly realizes something: the stolen objects match lines from the nursery rhyme 'Hickory Dickory Dock'. The clock (Hickory Road's name), the mouse (a small figurine), the bell (a stolen handbell), and so on. This discovery changes the investigation, providing a structure for the seemingly arbitrary thefts. He now believes the thief, and likely the murderer, is carefully following this pattern, using the rhyme as a twisted guide for their actions, possibly to mock investigators or as a reminder for a larger plan.
The Missing Rhyme Book
Poirot discovers that Celia Austin had a children's book of nursery rhymes, which has now vanished. He deduces that this book contains the specific version of 'Hickory Dickory Dock' the culprit uses as their guide. The book's disappearance is a major setback, preventing Poirot from fully understanding the killer's next moves or the complete list of items they plan to target. He suspects the murderer either stole or destroyed it to hide their method, further complicating the already complex puzzle and showing the killer's cleverness.
The Second Murder: Mrs. Nicoletis
The investigation takes another dark turn with the murder of Mrs. Nicoletis, an elderly resident who often spoke randomly about various things. She is found dead, also appearing to be from natural causes, but Poirot again suspects foul play. It becomes clear that the killer is removing anyone who might accidentally discover their secret or provide a key clue. Mrs. Nicoletis's death further strengthens the idea that the thefts were merely a cover for a much more serious criminal operation, and that the risks are incredibly high for the perpetrator.
The Smuggling Operation
Through careful investigation and observation of the residents, Poirot uncovers a sophisticated diamond smuggling operation running out of Hickory Road. The seemingly random stolen items, especially the diamond ring and a specific edition of a children's rhyme book, are connected to this illegal trade. The book, in particular, contains a hidden code or message essential to the operation. The petty thefts were staged to create confusion, diverting attention from the real criminal activity and allowing the smugglers to operate unnoticed.
The True Identity of the Mastermind
Poirot gathers all the suspects in the common room for his big reveal. He explains how the nursery rhyme was a memory aid for the smuggling operation and to confuse the police. He then names Nigel Chapman as the mastermind behind the diamond smuggling. Nigel, an outwardly charming and smart young man, had used the hostel as a base for his illegal activities, employing Celia Austin and others, who were either unaware pawns or forced participants. Celia's death was a desperate act to silence her after she became a problem or threatened to expose him.
The Motive and the Accomplices
Nigel's motive is pure greed, along with a desire for excitement and to prove his intelligence. This desire for wealth led him to plan elaborate schemes, manipulate those around him, and commit murder without remorse. Celia Austin and Mrs. Nicoletis became disposable obstacles in his pursuit of riches. The diamond ring, originally Celia's, was a crucial part of the smuggling puzzle. Valerie Hobhouse, another resident, was Nigel's accomplice, devoted to him and willing to take part in his plans. She helped him with the thefts and disposing of evidence, acting as his loyal, though misguided, partner in crime.
Justice is Served
With Poirot's detailed explanation, Nigel Chapman and Valerie Hobhouse are exposed and arrested. The full extent of their criminal enterprise, including the murders of Celia Austin and Mrs. Nicoletis, is revealed. The remaining students and Mrs. Hubbard are left to deal with the shocking truths. The hostel, once a place of study and youthful friendship, is forever marked by the crimes committed within its walls. Poirot, having again solved a complex and unique case, leaves, allowing the police to handle the formal procedures and the hostel to slowly recover from the ordeal.