In J.A. Bayona's emotionally explosive A Monster Calls, a young boy uses fantasy to reckon with the unbearable tragedy of losing his mother.

As Conor O'Malley (newcomer Lewis MacDougall) grows increasingly conflicted with the world around him, he begins to disappear into a realm where a large yew tree monster (voiced by Liam Neeson) helps him come to terms with the madness of his reality through a series of three stories. In this exclusive clip from the film, the Monster and Conor wreak havoc on a parson's house in a colorful dreamscape.

When Conor tells the Monster to break the windows, the giant yew tree looks at Conor and says, "Break them yourself." And so, with a little help from the Monster, he does.

For those who've read Patrick Ness's moving story of grief and loss — Ness also wrote the screenplay for the film — this is a pivotal part of the book that inspired the film. Through the Monster's tales, which progress from 2-D watercolor animation to 3-D, as you see here, Conor's fantasies become more lifelike as the lines between fantasy and reality start to blur and converge.

Still, these stories help Conor give meaning to all of the complicated emotions he's feeling, from blind rage to unimaginable sadness to unexpected relief.

A Monster Calls hits theaters on December 23, 2016.