Ready or Not is a 2019 American black comedy horror film directed by Matt Bettinelli-Olpin and Tyler Gillett and written by Guy Busick and R. Christopher Murphy. It stars Samara Weaving, Adam Brody, Mark O'Brien, Henry Czerny, and Andie MacDowell. It follows a young bride who is hunted by her spouse's wealthy Satan-worshipping family as part of a wedding night ritual.

Preparations began in November 2017 when Bettinelli-Olpin and Gillett, members of the Radio Silence filmmaking collective, were hired as directors. After setting an initial release date, casting occurred from August to October 2018. Principal photography began later that month and concluded in November, in locations in and around Toronto, Canada and the surrounding Ontario area.

Ready or Not premiered at the Fantasia International Film Festival on July 27, 2019, and was theatrically released in the United States on August 21, 2019, by Fox Searchlight Pictures. It received positive reviews from critics, who praised the performances of the cast, Bettinelli-Olpin and Gillett's direction, and screenplay. The film was a box office success, grossing $57.6 million worldwide against a $6 million budget. It was nominated for Best Horror Film at the 46th Saturn Awards.