Christopher John Francis Boone
Narrator and protagonist
Christopher is fifteen, brilliant at mathematics, and experiences the world with heightened sensory intensity. He cannot tolerate being touched, reads faces with difficulty, and insists on literal truth. Stephens and Haddon refuse to name a diagnosis, presenting Christopher’s perspective as coherent and complete rather than deficient. His detective investigation - modelled on Sherlock Holmes, whom he admires - drives the plot, but his real journey is towards independence. The London trip is the play’s coming-of-age sequence: Christopher navigates crowds, noise and the Underground using logic, Siobhan’s internalised voice, and sheer will. His final question - "Does that mean I can do anything?" - is left genuinely open.
"I find people confusing."
Ed Boone
Christopher’s father
Ed is a single parent doing his best under impossible pressure. He cooks Christopher’s meals in the right order, manages his routines, and shows fierce physical protectiveness. But he is also the man who killed Wellington, hid Judy’s letters, and told Christopher his mother was dead. Stephens presents Ed’s lies as coming from love - he wanted to shield Christopher from Judy’s departure - but the play does not excuse the damage. Ed’s confession scene is the play’s most painful moment: a father losing his child’s trust in real time.
"I love Christopher more than anything in the whole wide world."
Judy Boone
Christopher’s mother
Judy left the family because she could not cope with the demands of raising Christopher. Her hidden letters - discovered midway through the play - reveal a woman overwhelmed by her own inadequacy rather than lacking in love. She is impulsive, emotional and self-critical. When Christopher arrives at her London flat, she takes him in, but the play makes clear that she too will struggle. Stephens refuses to make her either a villain or a saint, presenting her departure as the result of exhaustion, not indifference.
"I wasn’t a very good mother, Christopher."
Siobhan
Christopher’s teaching assistant and narrator
Siobhan reads Christopher’s book aloud to the audience, functioning as both a character within the story and the play’s narrator. She is patient, calm and consistently respectful of Christopher’s boundaries. Her voice in Christopher’s head during the London journey represents the internalised guidance of a trusted adult. The metatheatrical frame - Siobhan is staging Christopher’s book as a school play - makes her the bridge between Christopher’s inner world and the audience’s understanding.
"It doesn’t have to have an ending. It’s a very good book."
Mrs Shears
Neighbour and Wellington’s owner
Mrs Shears’s dead poodle triggers Christopher’s investigation. She had a relationship with Ed after Judy left, which ended badly - Ed killed Wellington in a rage against her. Mrs Shears functions as the connecting point between the mystery plot and the family drama. Her anger at Christopher’s questions foreshadows the darker revelations to come.
"What in God’s name have you done to my dog?"
Mrs Alexander
Elderly neighbour
Mrs Alexander is the kindly neighbour who inadvertently gives Christopher the information about Ed and Mrs Shears’s affair, and about Judy’s affair with Mr Shears. She treats Christopher with genuine patience and warmth, offering him biscuits and conversation. She represents the ordinary decency of the neighbourhood and the way adult secrets leak through social interaction.
"Maybe you should ask your father about this."
Roger Shears (Mr Shears)
Judy’s partner in London
Roger Shears had an affair with Judy while still married to Mrs Shears, and Judy eventually left Ed to live with him in London. He is impatient with Christopher and does not understand his needs. His flat becomes the destination of Christopher’s journey but not a safe haven. Roger’s frustration with Christopher’s presence creates tension that ultimately pushes Judy to leave him and return to Swindon.
"He can stay for a few days."
Reverend Peters
Local vicar
The Reverend Peters appears briefly when Christopher asks him about heaven. Christopher’s literal response to the vicar’s metaphorical language highlights the play’s central tension between different ways of processing the world. The scene is comic but also philosophically serious.
"Well, when I say heaven, I don’t necessarily mean somewhere above."