Vengeance (Chinese: 復仇) is a 2009 action thriller film co-produced and directed by Johnnie To, and written by Wai Ka-Fai. It stars Johnny Hallyday, Anthony Wong, Gordon Lam, Lam Suet, Simon Yam, Michelle Ye and Sylvie Testud. The film tells the story of Francis Costello, a French chef and former assassin whose daughter, son-in-law and grandchildren are attacked by a gang of Triads. Costello travels to Macau to embark on a quest for revenge, enlisting the aid of three hitmen. The film explores the themes of assassination, violence and the influence of Triads in modern society. Produced by Milkyway Image, the film was released by ARP Sélection in France, and Media Asia Films in Hong Kong.

The idea of To directing an English-language film originated with ARP co-founders Michèle and Laurent Pétin, who had Alain Delon in mind for the lead role. In 2006, after Delon turned down the role, the Pétins recommended Hallyday, who was cast in the lead role after meeting with To in early 2008. Principal photography began in November 2008, and concluded in January 2009; filming took place on locations in Hong Kong and Macau, with a crew mainly based in Hong Kong.

Vengeance competed for the Palme d'Or at the 62nd Cannes Film Festival, and was released theatrically in France on 20 May 2009. The film was later released in Hong Kong on 20 August 2009. It premiered in North America at the 2009 Toronto International Film Festival. Vengeance was met with positive reviews, with several critics praising To's direction, Hallyday's performance, the cinematography and editing. During its theatrical run, the film grossed over US$1.3 million worldwide, having been released in Asia and parts of Europe. In the United States, the film was distributed by IFC Films, which made it available as a video-on-demand selection on pay television formats. The film was nominated for Best Original Film Score at the 29th Hong Kong Film Awards.