To take down South Boston's Irish Mafia, the police send in one of their own to infiltrate the underworld, not realizing the syndicate has done likewise. While an undercover cop curries favor with the mob kingpin, a career criminal rises through the police ranks. But both sides soon discover there's a mole among them.

Genres

Cast

Leonardo DiCaprio

Billy

Matt Damon

Colin

Jack Nicholson

Costello

Mark Wahlberg

Dignam

Martin Sheen

Queenan

Ray Winstone

Mr. French

Vera Farmiga

Madolyn

Anthony Anderson

Brown

Alec Baldwin

Ellerby

Kevin Corrigan

Cousin Sean

James Badge Dale

Barrigan

David O'Hara

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