A Monster Calls is a children's book written by Patrick Ness and published in 2011. It has received numerous awards, and a recent film adaptation has also garnered critical acclaim.

The book tells the story of Conor O'Malley, a 13-year-old boy whose mother is terminally ill. Over the course of the book, Conor is repeatedly visited by a monster who tells him different stories. These stories are reflections of fears and worries that Conor is experiencing in his everyday life. After he has ‘come around’ from these ‘visits’, Conor sees that somebody has engaged in destructive and violent behaviour, such as trashing his grandmother's lounge or assaulting a bully. Conor's memories are that he has seen the monster carry out these acts, even though the witnesses state it was Conor.

The story ends with Conor telling a story of his own, a recurrent nightmare in which his mother is dangling off a cliff edge and Conor is grabbing hold of her by her arm. Eventually, his mother's weight becomes too much to bear and he lets go, letting her fall. The monster helps him understand that it is all right for him to feel overwhelmed and worn-out by his mother's illness, and the fact that he has let go does not make him a bad son.

Assuming the monster is not real, Conor's actions throughout the book serve as a good example of dissociation. Conor displays this at numerous points by believing that it is not him acting, but the monster (external and independent from his self). During these events, Conor experiences feelings of dissociation and a sense of disconnect from himself; he describes the events as if he is watching from an outsider's perspective, seeing the ‘monster’ act in his stead.

The aetiology behind Conor's dissociation lies in the emotional trauma he deals with. As he finds it hard to acknowledge and express his feelings about his mother's terminal illness, they manifest as dissociative symptoms. Another precipitating factor is that Conor faces recurrent bullying at school and has few friends – indeed, one of the stories the monster tells reflects on the fact that Conor feels invisible in his school. This feeling of invisibility may serve as another factor that drives his sense of dissociation. Furthermore, he has little contact with his father (who lives in another country) and is often taken care of by his grandmother, whom he does not like.

A Monster Calls is an unusual book in the genre of children's fiction in that it deals with distressing topics such as terminal illness and bereavement. By portraying the subject in a sensitive and suitable manner, however, it provides an appealing experience to the younger reader who may be dealing with similar issues. The dissociation that Conor experiences is an engaging example of how feelings of disconnect can act as a coping mechanism during times of emotional trauma.