Mrs. Alexander is one of Christopher’s neighbors. She is an old lady who lives opposite Mrs. Shears. Christopher asks her if she knows who killed Wellington, the dog. Mrs. Alexander is kind to Christopher, engaging him in conversation. It is she who eventually explains to Christopher that his mother was having an affair with Mr. Shears, and that is why his father dislikes Mr. Shears.
Christopher Boone is a fifteen-year-old autistic boy who is the narrator of the novel, which he decides to write as a murder mystery after he discovers that someone has killed Wellington, his neighbor’s dog. Christopher lives with his father in Swindon, England. His mother left home because she was having an affair with a neighbor, Mr. Shears, but Christopher’s father told him his mother was dead. Christopher finds out the truth when he discovers in his father’s room unopened letters addressed to him from his mother. When his father confesses that it was he who killed the dog Wellington, Christopher is frightened of his father and decides to make a trip by train to London so that he can live with his mother instead.
Christopher attends a school for students with special needs, but he is something of a math genius, and he is very interested in science too. He likes order and logic, and tries to solve any problem using logic. He takes his A-level mathematics exam at the age of fifteen, three years earlier than most students do, and passes with the highest grade. He can remember an astonishing amount of facts and figures, and his ambition is go to university and eventually become a scientist. However, he has a much harder time handling feelings and emotions, which he does not understand well, so he is sometimes confused by what people mean when they talk to him. He finds it difficult to read people’s facial expressions. When he is frustrated or when there is too much sensory input to deal with, or too many questions are being asked of him by someone, he reacts by shutting himself off, making a groaning sound.
Christopher’s father (Ed Boone) runs a heating maintenance and boiler repair business in Swindon. After his wife left him to live with Mr. Shears, Ed was left to raise Christopher by himself. He is more patient with the boy than his wife was, and does his best to understand him, but he also finds his son exasperating. Ed cannot think of how to explain to Christopher why his mother is no longer there, so he tells him she is dead, and he hides the letters she sends to Christopher from London. He later apologizes for his deception. He also confesses that it was he who killed Wellington the dog, because he wanted to get back at Mrs. Shears. They had become close friends following the departure of his wife, but had quarreled. He thought she cared more about the dog than about him or Christopher, so in a rage he killed it. After this confession, Christopher is frightened of his father and goes to live with his mother. However, Ed makes every effort to make amends and to win back his son’s trust.
Christopher’s mother is more hot-tempered than his father, and she found raising Christopher to be a hard task. Sometimes she would yell at him, and at times she felt she could not go on. She and her husband got into arguments about it, and they grew apart. Christopher’s mother, feeling lonely, started to spend time with her neighbor, Mr. Shears, and they began an affair, which eventually led to her leaving home to live with him in London. She wrote to Christopher but his father does not pass her letters on to him. Eventually, Christopher’s mother breaks off her relationship with Mr. Spears, and returns to Swindon, where she and Christopher live together.
Mrs. Forbes is a teacher at Christopher’s school. Christopher thinks she is old. She appears not to have a good understanding of how to deal with Christopher, since she comments that Christopher’s dislike of the colors yellow and brown is “silly.”
Mrs. Gascoyne is the school headmistress, the equivalent of the principal in an American school. She makes special arrangements for Christopher to take his A-level exam in math.
Mr. Jeavons is the school psychologist. He tries to encourage Christopher by telling him he is clever. Christopher notes that Mr. Jeavons smells of soap and that his shoes have “approximately 60 tiny circular holes in each of them.”
Reverend Peters is a clergyman who sometimes comes to the school to talk to the students. Christopher cannot accept or understand what the Reverend Peters tells him about heaven and God, largely because it is neither logical nor scientific to him.
Rhodri is an employee of Christopher’s father. His wife has left him and has taken the children, so he sometimes comes to Christopher’s home to socialize. Sometimes he teases Christopher in a good-natured kind of way, but Christopher does not like it.
Mr. Shears (first name Roger) is a neighbor of Christopher’s and the husband of Mrs. Shears. However, he has left his wife and is living in London with Christopher’s mother. Christopher’s father dislikes him. In the end, he and Christopher’s mother break off their relationship acrimoniously.
Mrs. Shears (first name Eileen) is a neighbor of Christopher’s. She lives on the opposite side of the road. It is Mrs. Shears’s dog Wellington that is killed, leading Christopher to investigate. Mrs. Shears was kind to Christopher’s father after his wife went to live with Mrs. Shears’s husband in London. She did a lot of cooking and cleaning for him and Christopher and sometimes stayed overnight at their house. At one point Christopher’s father thought she might move in with him, but this never happened, and he no longer considers her a friend.
Siobhan is Christopher’s teacher at school. She understands him well and knows how to deal with him. He has known her for eight years, and he trusts her. It is Siobhan who encourages Christopher to write something that he would want to read himself, so Christopher sets about writing a murder mystery novel. Siobhan has long blonde hair and wears glasses with very thick lens.
Mr. Wise is one of Christopher’s neighbors. Christopher asks him if knows who killed Wellington, but Mr. Wise just makes a joke in response, which upsets Christopher.
Curious Incident : Characters