Saw is a 2004 American horror film directed by James Wan, in his feature directorial debut, and written by Leigh Whannell from a story by Wan and Whannell. It is the first installment in the Saw film series, and stars Whannell, Cary Elwes, Danny Glover, Monica Potter, Michael Emerson, Ken Leung, and Tobin Bell. The film tells a nonlinear narrative, revolving around the mystery of the Jigsaw Killer, who tests his victims' will to live by putting them through deadly "games" where they must inflict great physical pain upon themselves to survive. The frame story follows Jigsaw's latest victims (Whannell and Elwes), who awaken in a large, dilapidated bathroom, with one being ordered to kill the other to save his own family.
The screenplay was written by Whannell, who co-created the story with Wan in their respective screenwriting debuts. It was originally written in 2001, but after failed attempts to get the script produced in Wan and Whannell's home country of Australia, they were urged to travel to Los Angeles. In order to help attract producers they shot a low-budget short film of the same name from a scene out of the script. This proved successful in 2003 as producers from Evolution Entertainment were immediately attached and also formed a horror genre production label, Twisted Pictures. The film was given a small budget of $1.2 million and was shot in 18 days.
Saw was first screened on January 19, 2004, before being released in North America on October 29, 2004, by Lionsgate Films. The film received generally mixed reviews from critics but grossed more than $100 million worldwide to become one of the most profitable horror films since Scream (1996). The film has since gained a cult following and has been frequently credited as one of the most revolutionary horror films of all time. It was theatrically re-released, to select theaters, on October 31, 2014, to celebrate its tenth anniversary. The first sequel, titled Saw II, was released in 2005.
(Summary from Wikipedia)