The Departed is a 2006 American crime thriller film directed by Martin Scorsese and written by William Monahan. It is both a remake of the 2002 Hong Kong film Infernal Affairs and also loosely based on the real-life Boston Winter Hill Gang; the character Colin Sullivan is based on the corrupt FBI agent John Connolly, while the character Frank Costello is based on Irish-American gangster and crime boss Whitey Bulger. The film stars Leonardo DiCaprio, Matt Damon, Jack Nicholson, and Mark Wahlberg, with Martin Sheen, Ray Winstone, Vera Farmiga, Alec Baldwin, Anthony Anderson and James Badge Dale in supporting roles. The film takes place in Boston and the surrounding metro area, primarily in the South Boston neighborhood. Irish Mob boss Frank Costello (Nicholson) plants Colin Sullivan (Damon) as a spy within the Massachusetts State Police; simultaneously, the police assign undercover state trooper Billy Costigan (DiCaprio) to infiltrate Costello's mob crew. When both sides realize the situation, Sullivan and Costigan each attempt to discover the other's identity before they are found out. (Source: Wikipedia.org, CC BY-SA)