After the separation of his parents, Connor (Lewis MacDougall), a boy of 12 years, will have to take care of the reins of the house, because his mother (Felicity Jones) is sick of cancer. In this way, the child will try to overcome his fears and phobias with the help of a monster (Liam Neeson), but his fantasies will have to face not only with reality, but his cool calculating grandmother (Sigourney Weaver). With this new work JA Bayonne closes its trilogy on the maternofiliales relations, that began with "The orphanage" and continued with "The impossible".