Twilight is a 2008 American romantic fantasy film directed by Catherine Hardwicke from a screenplay by Melissa Rosenberg, based on the 2005 novel of the same name by Stephenie Meyer. It is the first installment in The Twilight Saga film series. The film stars Kristen Stewart as Bella Swan, a teenage girl, and Robert Pattinson as Edward Cullen, a vampire. It focuses on the development of Bella and Edward's relationship and the subsequent efforts of Edward and his family to keep Bella safe from another coven of vampires.

The project was in development for approximately three years at Paramount Pictures' MTV Films, during which time a film adaptation that differed significantly from the novel was written. Summit Entertainment acquired the rights to the novel after the project's stagnant development. Rosenberg wrote a new adaptation of the novel shortly before the 2007–2008 Writers Guild of America strike and sought to be faithful to the novel's storyline. Principal photography began in March 2008 and took 44 days, being completed on May 2; the film was shot in the states of Oregon and Washington.

Twilight premiered in Los Angeles on November 17, 2008, and was theatrically released in the United States on November 21, by Summit Entertainment. Despite receiving mixed reviews from critics, the film grossed over $407 million worldwide. It was released on DVD and Blu-ray Disc on March 21, 2009, and became the most purchased DVD of the year. The soundtrack was released on November 4, 2008. The Twilight: Director's Notebook was released on March 17, 2009 and was a #1 New York Times Best seller.

The film was followed by four sequels: New Moon (2009), Eclipse (2010), Breaking Dawn – Part 1 (2011), and Breaking Dawn – Part 2 (2012)