NOTE: All citations in this Study Guide refer to the Kindle edition of A Monster Calls, published September 27, 2011.

Patrick Ness’s YA novel A Monster Calls details the story of Conor O’Malley, a 13-year-old boy who is dealing with his mother’s illness. Her impending death hangs over the bulk of the book, and Conor must explore his own emotions through stories to find peace in her passing and how he feels about it.

The Monster, birthed from the yew tree on the hill, appears in Conor’s room one night. Conor feels like it will be scary—he refers to his “real” nightmare and the "real” fear—but the yew tree does not scare him. The Monster tells Conor he has come to tell him three stories. After that, he will hear a fourth story from Conor, and he promises the truth will come out in the process. Although Conor feels like he is dreaming, he sees evidence of the tree in his bedroom the next morning.

Conor’s mother is still in the house, but is too ill to do much. Conor feeds himself and goes to school, where he is bullied by a local boy and his friends. A girl named Lily is there to stand up for Conor, but he will not receive her help; in fact, he rejects her. Back at home, Conor’s mother warns him that his grandmother will be coming the next day to help them.

The Monster’s first story is about a prince that murders his young bride in order to stage a revolution to take down the queen, who is secretly a witch. The story confuses Conor; it is not clear who is good or bad in the story, and the Monster reminds him that life, stories, and people are all this way: neither all good nor all bad, but a mix of both.

Conor’s grandma arrives; she is cold and reserved and Conor feels more alone than ever. The boys at the school still pick at him, but he welcomes it. He tells Lily that he is angry that she knew first of his mother’s illness and told everybody, making everyone treat him strangely. This is why he rejects her friendship. After school Conor’s grandmother reports that his mother needed to go back to the hospital and that he will have to stay at her house for a few days.

Grandma’s house is meticulous and pristine and Conor does not feel comfortable there. At 12:07 the Monster visits and tells him the second tale, about an apothecary and a parson. They are at odds in the village, with the parson decrying the apothecary’s methods and refusing to allow him to use the village’s yew tree to make healing balms. When the parson’s own children fall ill, he tries to get the apothecary to help, even offering to go back on his beliefs to save them. The Monster destroys the parson’s house in the dream, telling Conor that the parson would not hold to his truth and how important it is to believe something and stick to it. Conor helps the Monster destroy the house because the release of anger feels good; when he wakes he finds he has destroyed much of his grandma’s sitting room. She returns home and rather than punish him, finishes the job in tears.

Conor’s father arrives from America. Conor keeps expecting “a talk” from the adults but they will not be honest with him. At school, the bully and his friends decide to ignore Conor rather than beat on him, and this is somehow worse. Conor’s mother confesses that she is on the very last treatment option available, but that she has hope because it comes from a yew tree.

The next day, the bully at school coldly tells Conor that he “no longer sees him.” Conor is enraged, and the Monster arrives for the third tale, in which a man who was invisible makes himself seen. In the dream state, the Monster beats the other boy, making himself seen. However, eventually Conor realizes that it was he who beat up the boy, and he is taken to the headmistress who will not punish him because of what is going on at home. Conor learns from the Monster that even though Conor made himself seen through his violence, his fellow students start to ignore him.

A few days pass with no improvement in his mother; she develops an infection in her lungs and sleeps most of the time. At school Conor’s friend Lily approaches him, telling him that she "sees” him. He is pulled from school to see his mother, who is not responding to treatment. Conor’s mother tells him that the yew tree medicine did not work, and that if Conor is angry at her and at the world and cannot talk to her, she understands. She drifts off to sleep and Conor asks his grandma to take him home so he can visit the yew tree.

Once at his home, Conor demands that the Monster explain why he did not heal his mother. The Monster responds that he came to heal Conor, not his mother. Conor’s actual nightmare appears, in which his mother is hanging over a cliff and Conor lets go of her hands. The truth is that Conor is tired of his mother’s illness and is ready for her to die, and he is plagued by guilt that he has somehow caused her demise. The Monster assures him this is not true, that his emotions are normal and expected and he needs Conor to acknowledge this so he can forgive himself and live his life.

Conor goes to the hospital and tells his mother that he does not want her to die; the final scene shows him standing by her bedside, awaiting her passing.