The following version of the novel was used to create this study guide: Penny, Louise. A World of Curiosities. Minotaur Books, November 29, 2022. Kindle.

In the thriller A World of Curiosities by Louise Penny, the 18th installment in the Chief Inspector Gamache series, a psychopathic serial killer uses an altered copy of a famous painting nicknamed A World of Curiosities to threaten Armand Gamache and his family. The altered painting contains triggers that the killer, John Fleming, knows will upset Gamache and remind Gamache of the role he played in keeping Fleming in jail. Gamache had promised Fleming an early release if Fleming helped with an investigation, but Gamache reneged at the last minute. In the meantime, Fleming put together an intricate plan to escape jail and punish Gamache and Gamache's family for Gamache not keeping the promise.

A treasure trove, including a painting, was found in a bricked-up portion of Myrna Landers’s loft when she decided to expand that space. The painting was identified as a copy of a famous painting known as The Paston Treasure, or A World of Curiosities. This copy included modern items that did not exist when the piece was originally painted, indicating that it had been altered.

Meanwhile, Fiona Arsenault and her brother (Sam) are visiting the village of Three Pines after Fiona’s graduation from engineering school. The characters are significant because Sam and Fiona were involved in the murder of their mother, Clotilde Arsenault, when they were young children. Sam accused his sister of formulating the plan to kill their mother by hitting her in the head with a brick. She was found guilty of manslaughter and was sentenced to 12 years in prison. Gamache, however, was never entirely sure that the murder had been Fiona’s idea. From the beginning of his relationship with Sam, Gamache believed Sam was a psychopath, a boy with no conception of right and wrong. In the present, Gamache was already spooked by Sam’s presence in the village of Three Pines when the painting was discovered.

As Gamache studied the strange painting, he noticed the faces of the seven people Fleming had murdered included in the work. The presence of those faces made him certain that Fleming was involved in the painting in some way. He visited the jail where Fleming was being held and discovered the man the warden claimed was Fleming was an impostor. Fleming had escaped the jail. Strange markings on the painting turned out to be shorthand that read “I’m coming for you” (290), suggesting Fleming had plans to hurt Gamache and his family.

Fleming, disguised as the minister in Three Pines, coordinated his attack on Gamache, his wife, and his son-in-law so that he could kill them at the same moment that Gamache reneged on his promise to let Fleming out of jail. Sam and Fiona were helping Fleming with his plan. Sam hit Fleming, who was believed to be the minister, in the head with a brick so that Gamache would feel called to invite the minister to spend the night with him. Fiona, who stayed with the Gamaches, let Sam into the basement of the house when she came home for the evening.

While Gamache left the minister under the care of his son-in-law, Jean-Guy Beauvoir, to go and study the painting once again, Beauvoir was hit in the head and tied up. The minister, whom Gamache finally recognized was Fleming, brought Gamache’s wife to him at knifepoint. He took them all back to Gamache’s house where Sam and Fiona were supposed to act as backup.

When Sam learned that officers were coming to save Gamache before the exact moment came that Fleming wanted to kill him, Fiona went outside to watch for the officers. Instead of directing the officers away from the house, Fiona told them where Gamache and the others were. One of the officers shot Sam just before he could kill Beauvoir or Gamache’s wife. Meanwhile, Gamache overpowered Fleming and hit him in the head with a brick, killing him.