Jonathan Tucker Jonathan Tucker

He Plays: Jay Kulina, the drug-addled, deeply sensitive MMA fighter battling his distant, hard-assed gym-owner father (Frank Grillo) and his own demons on DirecTV's Kingdom. "The gym gives Jay discipline and keeps him away from his addictions," Tucker, 32, says of Jay's sweaty Season 1 evolution from burnout to potential champion. "He ultimately ends up realizing who he is and what he's done. [But] he needs to ask for help from his dad, and that is the hardest thing for him to do."

Where You've Seen Him: Tucker first earned notices from critics as Tommy Donnelly, the artistic Hell's Kitchen local trying to keep his small-time mob family from imploding on NBC's short-lived 2007 drama The Black Donnellys. Since then, the former Boston Ballet member has popped up in guest spots on White Collar, Hannibal, Person of Interest and, most recently, as politician Bob Little on Parenthood.

Why We Love Him: Shredded like lettuce and not afraid to show it, tucker bares more than just his ripped physique in Kingdom. "You have to love Jay because he does some pretty awful things, but there is a vulnerability that Tucker really brings to the role," executive producer Byron Balasco says. "He grounds it in humanity and emotion." Anyone seeking proof of that needs to look no further than the beautifully played scenes of Tucker's brutal warrior tenderly reconnecting with and caring for his strung-out mother (Joanna Going). "It's growing into a really lovely thing," says Going of their on-screen relationship.

Blood and Sweat, No Tears: Before stepping into Kingdom's ring, Tucker already had a cheering section in costar Matt Lauria, a fellow Parenthood alum. "Part of the draw was that Tucker was doing the show," says Lauria, who plays Jay's best bud and potential competitor, Ryan. "I had seen his work, but we never got to work together." Now, the two get to work and play, since their roles entail some serious training, as well as some serious injuries. "I ripped my cartilage from my ribs doing jujitsu," Tucker reports with no small amount of pride. "The split on my forehead is nothing compared to that." Fight on, kid!

Kingdom airs Wednesdays at 9/8c on DirecTV's Audience Network.

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