Blade Runner is a 1982 American science fiction film, directed by Ridley Scott and starring Harrison Ford, Rutger Hauer, and Sean Young. The screenplay, written by Hampton Fancher and David Peoples, is based on the novel Do Androids Dream of Electric Sheep? by Philip K. Dick. The film depicts a dystopian Los Angeles in November 2019 in which genetically manufactured beings called replicants — visually indistinguishable from adult humans — are used for dangerous or menial work on Earth's "off-world colonies". Following a replicant uprising, replicants become illegal on Earth and specialist police called "blade runners" are trained to hunt down and "retire" escaped replicants on Earth. The plot focuses on a brutal and cunning group of recently-escaped replicants hiding in Los Angeles and the semi-retired blade runner, Rick Deckard (Harrison Ford), who reluctantly agrees to take on one more assignment.

Blade Runner initially polarized critics: some were displeased with the pacing, while others enjoyed its thematic complexity. The film performed poorly in North American theaters. Despite the box office failure of the film, it has since become a cult classic. Blade Runner has been hailed for its production design, depicting a "retrofitted" future.Sammon, p. 79 It remains a leading example of the neo-noir genre. Blade Runner brought the work of author Philip K. Dick to the attention of Hollywood, and several more films have since been based on his work.Bukatman, p. 41 Ridley Scott regards Blade Runner as "probably" his most complete and personal film. In 1993, Blade Runner was selected for preservation in the United States National Film Registry by the Library of Congress as being "culturally, historically, or aesthetically significant". In 2007, the American Film Institute named it the 97th greatest American film of all time in the 10th Anniversary edition of its 100 years... 100 Movies list.

Seven versions of the film have been shown, for various markets, and as a result of controversial changes made by film executives. A rushed Director's cut was released in 1992 after a strong response to workprint screenings. This, in conjunction with its popularity as a video rental, made it one of the first films released on DVD, resulting in a basic disc with mediocre video and audio quality. In 2007, Warner Bros. released in select theaters and DVD/HD DVD/Blu-ray, the 25th anniversary digitally remastered definitive Final Cut by Scott.