Split is a 2016 American psychological thriller film written, directed and produced by M. Night Shyamalan, and starring James McAvoy, Anya Taylor-Joy, and Betty Buckley. The film follows a man with dissociative identity disorder who kidnaps and imprisons three teenage girls in an isolated underground facility.

Principal photography began on November 11, 2015, in Philadelphia, Pennsylvania. The film premiered at Fantastic Fest on September 26, 2016, and was released in the United States on January 20, 2017, by Universal Pictures. It received generally positive reviews; critics highly praised McAvoy's performance, and welcomed Shyamalan's direction. Some mental health advocates criticized the film for its stigmatization of mental illness. Split was a commercial success, grossing $278 million worldwide on a budget of $9 million, becoming Blumhouse Productions' highest-grossing film until 2023 when Five Nights at Freddy's overtook it.

Split is a standalone sequel to Shyamalan's 2000 film Unbreakable although not marketed as such, instead saving the revelation for a scene featuring Bruce Willis reprising his Unbreakable role in an uncredited cameo. Commentators dubbed Split the first-ever "stealth sequel", and the first solo supervillain origin film. The 2019 film Glass, which combined the casts and characters of both previous films, concluded Shyamalan's Unbreakable trilogy.