Nicky Cottero (Kirk Acevedo) is the right-hand-man of the town's mob boss. He'll eventually become disgruntled with the way things are run and will deal with "The Black Donnellys" on his own terms.
Sean Donnelly (Michael Stahl-David) is the baby brother who all the girls go ga-ga for. It won't be too long until he's thrust into the mobster scene that is "The Black Donnellys."
Jimmy Donnelly (Thomas Guiry) has a severe limp from a childhood accident. He's the oldest Donnelly brother, but is always breaking the law in more ways than one. Jimmy lives for and is willing to die for "The Black Donnellys."
Kevin Donnelly (Billy Lush) is the compulsive gambler in "The Black Donnellys." Unfortunately, he has yet to win a bet or a round of poker. His addiction has a way of putting the entire family in harms way.
Joey "Ice Cream" (Keith Nobbs) knows a lot about "The Black Donnellys." He always seems to be around the brothers, but manages to keep his distance when things get ugly.
Tommy Donnelly (Jonathan Tucker) is the second-oldest brother of "The Black Donnellys." He has great artistic talent, but is unable to pursue that love because he always puts his troublesome brothers above his own happiness.
Jenny (Olivia Wilde) has always been the one constant force in the lives all four of "The Black Donnellys." Jenny's in love with Tommy Donnelly, even though she believes that she's still married to a schoolteacher who everyone else knows is actually dead.