The Kid Who Would Be King is a 2019 urban fantasy action-adventure film written and directed by Joe Cornish. A British/American venture, the film stars Louis Ashbourne Serkis, Tom Taylor, Dean Chaumoo, Rhianna Doris, Angus Imrie, Rebecca Ferguson, and Patrick Stewart. The plot follows a young boy who finds King Arthur's legendary sword Excalibur and must use it to stop an ancient enchantress from enslaving the world with help from his classmates (and former bullies) from school.

It was distributed and created by 20th Century Fox in association with Working Title Films. The film was released in the United States on 25 January 2019, and in the United Kingdom on 15 February 2019.

Despite receiving positive reviews, the movie underperformed at the box office, with estimated losses for the studio ranging as high as $50 million. It was also the second to last film to be released by 20th Century Fox (after Alita: Battle Angel) before The Walt Disney Company took over of the studio as part of their acquisition of 21st Century Fox on 20 March 2019.