The true story of Troy Duffy, a brash, foul-mouthed bartender whose screenplay for an action film (Boondock Saints) scores him a generous contract to write and direct the film at Miramax Studios. Duffy's band, the Brood, is also in the midst of signing a contract with Madonna's Maverick Records. Duffy's fiery manner is instrumental to his success, but when the deals go sour, no one seems safe from his explosive temper.

For the past eight years, the MacManus brothers have been living with their father on a remote sheep farm in Ireland, far removed from their past vigilante lifestyle. When their uncle informs them that their beloved priest has been killed by the mob, and they are being framed for the murder, the duo return back to Boston to, not only, bring justice to those who are responsible, but clear their names.