Once a Thief is a 1991 Hong Kong heist comedy film directed by John Woo, who also wrote the screenplay with Janet Chun and Clifton Ko. The film stars Chow Yun-fat, Leslie Cheung, Cherie Chung, Kenneth Tsang and Paul Chu. The film was released theatrically in Hong Kong on 2 February 1991, before the lucrative Chinese Lunar New Year holiday season begins.