Its title refers to an observation by the fictional detective Sherlock Holmes (created by Arthur Conan Doyle) in the 1892 short story "The Adventure of Silver Blaze".

[5] The novel is narrated in the first-person by Christopher John Francis Boone, a 15-year-old boy who is described as "a mathematician with some behavioural difficulties" living in Swindon, Wiltshire.

In July 2009, Haddon wrote on his blog that "The Curious Incident is not a book about Asperger's ... if anything it's a novel about difference, about being an outsider, about seeing the world in a surprising and revealing way.

While searching his father's room for the book, Christopher finds letters from his mother dated after her supposed death, and eventually realises that she is still alive and living in London with Mr. Shears.

After a long, event-filled journey, evading policemen and feeling ill from the trains and crowds around him, he finally finds his way to the home of his mother and Mr. Shears, much to the delight of the former and chagrin of the latter.

In a 2004 interview, Haddon said I have to say honestly that I did more research about the London Underground and the inside of Swindon Railway Station, where some of the novel takes place, than I did about Asperger's syndrome.

[10] Muller adds that the novel works with a strong sense of the disabled speaking subject, drawing readers into Christopher's cognitive / corporeal space through an incremental layering of his perspectives and reactions ...

She also admires such elements as the digressive stream-of-connectedness-and-disconnectedness way in which Christopher writes and thinks; the obsessive focus on minutiae; his musings about why animals behave the way they do; his quasi-philosophizing on death and life and the afterlife; his ambition to be an astronaut ...[11] In a survey of children's books which "teach about emotional life", Laura Jana wrote: On the one hand, this is a story of how an undeniably quirky teenage boy clings to order, deals with a family crisis, and tries to make sense of the world as he sees it.

Filled with humor and pain, it verges on profundity in its examination of those things—customs, habits, language, symbols, daily routines, etc.—that simultaneously unite and separate human beings.

"[31] A reviewer for The Atlanta Journal-Constitution wrote that the story is "a touching evolution, one that Haddon scripts with tenderness and care ... a unique window into the mind of a boy who thinks a little differently, but like many kids his age, doesn't quite know how to feel.

"[33] Cathy Lowne of the Encyclopædia Britannica wrote that "Haddon's skill lies in writing so that, although Christopher may be unaware of emotional undercurrents and nuances of mood, the reader is made aware of them.

[35] Alex McClimens, whom Muller quoted above, also wrote: "This magnificent essay in communication is compulsory reading for anyone with the slightest interest in autistic spectrum disorders.

This book is also required reading for those who simply enjoy a fascinating story ... we are offered a first person narrative to match anything by contemporary writers.

Mark Haddon has created a true literary character and his handling of the teenage Asperger's heroic adventure is brilliantly crafted.

"[37] Reviewer David Ellis, naming The Curious Incident an "ambitious and innovative novel", wrote that Haddon "manages to avoid the opposing pitfalls of either offending people with autism and their families or turning Christopher into an object of pity.

[38] The Curious Incident of the Dog in the Night-Time has frequently been challenged due to its offensive language, supposed unsuitability for younger readers, and religious viewpoint.

[42] It starred Luke Treadaway as Christopher, Nicola Walker as his mother Judy, Paul Ritter as his father Ed, Una Stubbs as Mrs Alexander and Niamh Cusack as Siobhan.

In 2015 the cast was Sion Daniel Young as Christopher Boone, with Rebecca Lacey as Siobhan, Nicolas Tennant as Ed, Mary Stockley as Judy, Jacqueline Clarke as Mrs Alexander, Indra Ové as Mrs Shears, Stephen Beckett as Roger Shears, Matthew Trevannion as Mr Thompson, Pearl Mackie as No.

[50][51] An adaptation and translation into Spanish by María Renée Prudencio played at the Teatro de los Insurgentes in Mexico City in June 2014.

[52] An adaptation and translation into French by Dominique Hollier premiered at the Théâtre de la Tempête in Paris, directed by Philippe Adrien, running from September 11 through 18 October 2015.

An adaptation and translation into Danish by Christian Bundegaard premiered at the Odense Teater, September 2019, starring Kristoffer Helmuth as Christopher.