A Monster Calls is a 2016 dark fantasy drama film directed by J. A. Bayona and starring Lewis MacDougall, Sigourney Weaver, Felicity Jones, Toby Kebbell, and Liam Neeson. Featuring a screenplay adapted by Patrick Ness from his own 2011 novel of the same name, the film follows a boy grappling with his mother's terminal illness who is visited and told stories by a giant anthropomorphic yew tree.

The film rights to Ness' novel were acquired by Focus Features in March 2014, after which he was hired as screenwriter and Bayona signed on as director. Jones was cast that April, Neeson joined the film in May, and the rest of the main roles were cast by September. Principal photography began on 30 September, with filming taking place primarily in West Yorkshire, Derbyshire, and Lancashire in England, as well as in Bayona's native Spain.

After premiering on 10 September 2016 at the Toronto International Film Festival, the film was theatrically released on 7 October in Spain by Universal Pictures, on 1 January 2017 in the United Kingdom by Entertainment One, and five days later in the United States by Focus Features. It received positive reviews from critics, with praise for Bayona's direction, the acting, the visual effects, and the thematic content, but underperformed at the box office, grossing $47 million worldwide.