In the official trailer for the drama A Monster Calls, a lonely boy named Connor (Lewis MacDougall) is greeted by the voice of a monster who claims to know everything about him – the truth that he dreams and the truth that he hides. His mother (Felicity Jones), who is suffering from an illness, tells him about a tree that has been there for thousands of years. When the tree comes to life, it calls out to Connor and takes him away to a place beyond his imagination.