Cat Among the Pigeons

A revolution takes place within Ramat, a fictional kingdom in the Middle East. Knowing that he is unlikely to survive the violence, Prince Ali Yusuf entrusts his best friend and pilot, Bob Rawlinson, to smuggle a fortune in jewels out of the country. Rawlinson conceals the gems within the hollow of the handle of a tennis racquet belonging to his niece Jennifer, the daughter of his sister Joan, without telling them. Unbeknownst to him, a mysterious woman watches him from the neighbouring balcony.

The Prince and Rawlinson die in a plane crash while attempting to flee Ramat. Three months later, Jennifer prepares to attend Meadowbank School, a prestigious girls' independent school in England. Its staff includes Miss Bulstrode, the school's founder and headmistress; Miss Chadwick, a co-founder of the school and teacher of mathematics; Miss Vansittart, who has taught German at the school for several years; Miss Rich, who has taught English Literature at the school for 18 months; Miss Johnson, the girl's matron; Miss Angèle Blanche, the new French teacher; Grace Springer, the new gym teacher; Ann Shapland, Miss Bulstrode's new secretary; and Adam Goodman, a new gardener. As Miss Bulstrode is nearing retirement, she is deciding upon her successor. She believes Miss Chadwick is too old to take over, and is considering both Miss Vansittart, who behaves almost like a second edition of Miss Bulstrode, and Miss Rich, who is young and has many ideas of her own.

One night, Miss Chadwick and Miss Johnson notice a light in the sports pavilion and hear a gunshot; upon investigating, they find Miss Springer murdered. When the police begin to investigate, Goodman reveals to Inspector Kelsey, and later to Miss Bulstrode, that he works for British Intelligence. He is at Meadowbank to track down the gems Rawlinson smuggled out, by monitoring Prince Ali Yusuf's cousin, Shaista, who is attending the school. Meanwhile, Jennifer complains to her friend Julia Upjohn that her racquet no longer feels balanced, and they swap racquets. Later, a strange woman approaches Jennifer to present her with a new racquet, claiming it is from Jennifer's aunt, Gina, and takes the old racquet in exchange. However, the sharper Julia finds this suspicious, and aunt Gina later writes to reveal that she had not sent Jennifer a new racquet.

The following weekend, Shaista is kidnapped by someone posing as her uncle's chauffeur. That night, Miss Vansittart is murdered with a sandbag in the sports pavilion. After Jennifer and many other students are fetched home by worried parents, Julia investigates the racquet she swapped with Jennifer and finds the smuggled jewels. When someone attempts to enter Julia's room during the night, she quickly flees the school to tell her story to Hercule Poirot, whom she has heard stories about from her aunt, Maureen.

While Poirot is at Meadowbank investigating the murders, Miss Blanche is murdered with a sandbag. Interviewing Miss Bulstrode, Poirot learns that Julia's mother, Mrs Upjohn, who once worked in British counterintelligence during the war, recognised a fellow agent at the school on the first day of term.

Poirot eventually reveals to all that the Shaista who attended Meadowbank was an imposter; the real Shaista was kidnapped by a group seeking Prince Ali Yusuf's jewels. When the imposter did not find them, the group extracted her from the school before the uncle of the real Shaista could expose her. Poirot briefly focuses attention on Miss Rich as a potential suspect, so he can put the true murderer at ease. He then reveals that Miss Springer was killed because she caught the killer searching for the tennis racquet. Miss Blanche was killed when she attempted to blackmail the killer.

Through Mrs Upjohn, Poirot identifies Ann Shapland as a ruthless espionage agent known as "Angelica". Miss Shapland had been in Ramat three months earlier, and was the woman who had witnessed Rawlinson concealing the gems in Jennifer's racquet. Before Miss Shapland is arrested, she attempts to shoot Mrs Upjohn. As Miss Bulstrode tries to shield Mrs Upjohn, Miss Chadwick steps in to protect Miss Bulstrode and is fatally wounded. Miss Shapland is disarmed and taken away. Poirot then reveals that the second murder was committed by Miss Chadwick, who was jealous of Miss Vansittart's better qualifications as Mrs. Bulstrode's possible successor. Miss Chadwick came upon Miss Vansittart alone in the sports pavilion, and struck her down in a fit of madness.

In the aftermath of the investigation, Miss Bulstrode appoints Miss Rich as her partner and successor, with both focusing on rebuilding Meadowbank and its reputation. Meanwhile, Poirot turns over the gems to a Mr Robinson, who turns them over to Prince Ali Yusuf's secret wife; they had married and had a son while Yusuf was a student in England. Julia Upjohn receives an emerald as a reward.