Simon Dillon reviews the impressive and moving adaptation of the novel by Patrick Ness.

Is A Monster Calls a children's film about loss, an adult film about a child's grief, or something in between? After watching JA Bayona's undeniably impressive and moving adaptation of the novel by Patrick Ness, I am still unsure.

Conor (newcomer Lewis MacDougall) is a quiet and highly imaginative adolescent boy, struggling to look after his terminally ill mother (Felicity Jones). He is also bullied at school. One day he summons a tree monster (a cross between an angry Ent and a much bigger, scarier Groot, voiced by Liam Neeson), who informs Conor that he will tell him three stories, before he must in turn tell the monster his story and "the truth" about a recurring nightmare he is experiencing.

Lewis MacDougall is quite a find, Felicity Jones is heartbreaking, and even though I was unsure of her accent at first, Sigourney Weaver contributes a fine supporting performance as Conor's strict grandmother. Toby Kebbell is also good as Conor's largely absent LA based father, and Liam Neeson's monster is terrific, as are the special effects used to create him.

In adapting his own novel, Patrick Ness's screenplay sticks very closely to the book, excising only one minor subplot involving Conor's friendship with a girl in his class. Otherwise the events are identical; an uncompromising study of a child dealing with seemingly inescapable impending grief, even though he desperately hopes his mother will recover from her illness. Bayona (who also directed The Orphanage and The Impossible) helms with a sure hand and makes fine use of the widescreen frame. He occasionally emulates Del Toro, particularly Pan's Labyrinth, and even Spielberg, with some of the home invasion stuff reminding me of Close Encounters of the Third Kind and more recently The BFG.

A Monster Calls has interesting things to say about the way children grieve, mostly during the allegorical tales told by the monster (rendered, incidentally in splendid watercolours). For example, it examines the way children look for someone to blame (in the same way many adults do) but come to learn that real life contains very few outright heroes or villains. Furthermore, the story touches on processing difficult emotions such as guilt. It also reassures without patronising or minimising pain, that despite loss, life continues and better times can lie ahead. It even hints at how sometimes pain can be borne more easily by looking to help others who are also suffering.

All of this makes the film sound rather heavy and depressing, and frankly on one level it absolutely is. It might be too upsetting for some (perhaps many) younger children, but I also suspect children who have suffered the loss of a parent might find the film empowering and cathartic.

Commercially, A Monster Calls is unlikely to hit any obviously large demographic, which is a shame as it is a very fine piece of work that I like very much. It is, ultimately, a wise, compassionate, empathic, emotionally honest film with its heart absolutely in the right place.