A Better Tomorrow is a 1986 Hong Kong action film directed, co-written, and co-produced by John Woo; co-produced by Tsui Hark; and starring Ti Lung, Leslie Cheung and Chow Yun-fat. The film had a profound influence on Hong Kong action cinema, and has been recognised as a landmark film credited with setting the template for the heroic bloodshed genre, with considerable influence on both the Hong Kong film industry and Hollywood.

The action film is a film genre that predominantly features chase sequences, fights, shootouts, explosions, and stunt work. The specifics of what constitutes an action film has been in scholarly debate since the 1980s. While some scholars such as David Bordwell suggested they were films that favor spectacle to storytelling, others such as Goeff King stated they allow the scenes of spectacle to be attuned to story telling. Action films are often hybrid with other genres, mixing into various forms ranging to comedies, science fiction films, and horror films.