The following edition of the text was used in the creation of this study guide: Twan Eng, Tan. The House of Doors. Canongate, 2023. Kindle AZW file.

In the Prologue, set in 1947 South Africa, Lesley received an unexpected parcel—a book by Somerset Maugham—which stirred memories of her past with her late husband, Robert. Lesley reminisced about a visit to Penang in 1921 involving Maugham, known throughout the novel as Willie, and his secretary, Gerald.

In Book One, the narrative unfolds in Penang, where Willie woke up in the home of Robert and Lesley. Willie learned of his financial troubles through a letter and discussed his work with Lesley, uncovering her ties to the Chinese revolutionary Sun Yat Sen. Tensions escalated as Lesley grappled with Robert's desire to move to South Africa for his health. Upon Willie's arrival with his secretary, Gerald, Lesley observed their homosexual relationship, of which she disapproved. Meanwhile, Lesley’s conversation with Willie inspired her to try to locate Sun Yat Sen. Willie explored Cassowary House's library and found books about China inscribed to Lesley from 1910. Willie recalled leaving his wife for Gerald. Seeking Sun Yat Sen, Lesley enlisted her brother Geoff’s help. Willie hid his financial woes from Gerald, sharing his family's history with Lesley, who contemplated legacy and storytelling. At a party, Willie observed Lesley's encounter with a Chinese man, discussing storytelling afterward. Learning more about the whereabouts of Sun from the man, Lesley promised to get Willie's signature for the man's son's book. Later, she and Willie discussed the symbol in his books, and Lesley opened up about her life.

In Book Two, Lesley tells Willie her life story, beginning in Penang in 1910. She recalled Robert's introduction to Sun Yat Sen, a Chinese revolutionary, and her friend Ethel's arrest for murder. Determined to support Ethel, Lesley visited her in Kuala Lumpur, recalling their previous conversations about Ethel's affair. Meanwhile, Lesley's brother Geoff delivered news of Robert's infidelity, prompting Lesley to reflect on their past happiness and consider divorce. At a social gathering, they encountered Sun Yat Sen and his associate, a Chinese man named Arthur Loh. Lesley also visited Ethel in prison, promising to safeguard her secret. Moving forward to 1921, Willie began to suspect Lesley's had an affair with Sun and shared the news of his financial woes with Gerald. Lesley met Willie to continue their discussion. In 1910, she found herself drawn into Sun's cause despite Robert's objections, forging a connection with supporter Arthur Loh. Amidst her clandestine activities, Lesley stumbled upon evidence of Robert's own affair. In Penang in 1921, Willie faced Gerald's complaints about his impending return to England due to his financial problems, hindered by Gerald's legal issues linked to his homosexuality. In 1910, Lesley attended a talk by Sun Yat Sen at Arthur's house, and afterwards Lesley and Arthur began an affair. They met at a property owned by Arthur, which he called The House of Doors because he used it to house his collection of painted doors. Ethel Proudlock's lawyer asked Lesley to testify at her trial.

Returning to 1921, Willie assisted the ill Robert, who hinted at Ethel's case, implicating her husband and father. In 1910, Lesley testified in Ethel's trial, lying about her knowledge of Ethel's affair. Ethel was found guilty of murder and was sentenced to death. Back in 1921, Willie pressed Robert about his comments regarding Ethel, but Robert denied any recollection. Sun Yat Sen faced expulsion from Penang by the authorities, bidding farewell to Arthur and Lesley at the docks. Arthur revealed a symbol on the House of Doors, which also featured on the front of Somerset Maugham's books. Arthur announced his decision to leave Penang to fight for Sun’s revolution in China. Lesley made Arthur promise never to contact her by letter so as not to reveal her infidelity. Lesley gifted Arthur a necklace with the symbol from the House of Doors, retaining her key. Meanwhile, Ethel received a pardon from the Sultan and left for England with her daughter, cryptically stating, "He made me do it," to Lesley. One morning, Robert announced a revolution in China, with Sun as president.

In Book Three, Willie contemplated writing about Lesley's tales, while Lesley showed him the symbol on the House of Doors. The Epilogue, set in 1947 South Africa, sees Lesley reflecting on her life with Robert after his death and receiving a copy of Maugham's book. Lesley recognizes the book as a message from Arthur due to the altered symbol on its cover, mirroring the one carved on the House of Doors. Its presence on the book suggests Arthur's return to Penang.