Saw (2004)

Most people think so. 82% of audiences gave it a thumbs up, by Google's archived audience score. Critics scored it lower at 48%, but audiences disagreed.

Two men wake up to find themselves shackled in a grimy, abandoned bathroom. As they struggle to comprehend their predicament, they discover a disturbing tape left behind by the sadistic mastermind known as Jigsaw. With a chilling voice and cryptic instructions, Jigsaw informs them that they must partake in a gruesome game in order to secure their freedom. Wikipedia ↗

Saw is a 2004 American horror film directed by James Wan and written by Leigh Whannell, the debut feature that launched one of the most successful horror franchises in history. The film follows two men — Dr. Lawrence Gordon played by Cary Elwes and photographer Adam Stanheight played by Leigh Whannell — who wake up chained to pipes in a derelict industrial bathroom with a dead body between them and a tape recorder that explains they are players in a game devised by the Jigsaw Killer, a serial killer who doesn't technically murder his victims but places them in elaborate, deadly traps designed to test their will to live.

James Wan and Leigh Whannell made Saw on an extremely low budget of approximately $1.2 million, and the constraints forced inventive filmmaking — the bathroom setting kept production costs down while the fragmented, time-jumping narrative structure built tension through what was implied rather than shown. Tobin Bell's performance as John Kramer/Jigsaw, revealed through flashbacks, created one of horror's most compelling modern villains — a terminally ill man who believes his victims don't appreciate their lives and designs his traps as twisted tests of survival. The film's twist ending, in which the "corpse" in the bathroom rises from the floor, was one of the most shocking reveals in modern horror.

Saw earned $103 million worldwide on its minimal budget and spawned nine sequels, collectively grossing over $1 billion.