When police interviews fail to turn up a clear suspect, Charles agrees to help his father, an Assistant Commissioner of Scotland Yard, investigate the crime. All the family members hope these two prove to be the murderers because they despise Brenda as a gold digger and also hope to escape the scandal that a different outcome would bring. Rumour has it that Brenda and Laurence have been carrying on an illicit love affair right under old Leonides' nose. The obvious suspects are Brenda Leonides, Aristide’s much younger second wife, and Laurence Brown, a conscientious objector who has been living in the house as private tutor to Eustace and Josephine, Sophia's younger brother and sister. When the autopsy reveals that Aristide Leonides has been poisoned with his own eserine-based eye medicine via an insulin injection, Sophia tells Charles that she can't marry him until the matter is cleared up. Due to the war, the whole family has been living with him in a sumptuous but ill-proportioned house called ' Three Gables' - the crooked house - of the title. Hayward returns home only to find an obituary in The Times: Sophia’s grandfather, the wealthy entrepreneur Aristide Leonides, has died, aged 85. They fall in love, but put off getting engaged until after the end of the war when they will be reunited in England. There he meets Sophia Leonides, a smart, successful young Englishwoman who works for the Foreign Office. The first person narrator is Charles Hayward who, towards the end of the Second World War, occupies some post in Cairo. (may contain spoilers - click on expand to read) When sly Josephine suffers attack and Nanny is poisoned by hot chocolate after Brenda and the tutor are arrested, the danger escalates to a surprise finish. Charles' father 'The Old Man' is the Assistant Commissioner of Scotland Yard, so Charles investigates from the inside along with assigned detective, Chief Inspector Taverner. After Aristide is poisoned by his own eye medicine ( eserine), his granddaughter Sophia tells narrator and fiancé Charles Hayward that they cannot marry until the killer is apprehended.

Second wife indolent Brenda, decades his junior, exchanges love letters with grandchildren's tutor. His first wife died her sister Edith has cared for the household since then. Three generations of the Leonides family live together under wealthy patriarch Aristide. twisted and twining' unhealthily interdependent on the intensely strong personality of the family patriarch Aristide.

Narrator Charles' fiancée Sophia says not dishonest rather 'we hadn't been able to grow up independent. The title refers to (' There Was a Crooked Man') nursery rhyme, a common theme of author. 6.1 References to actual history, geography and current science.

Agatha christie charles hayward