THE world of mixed martial arts, or MMA, seems like a violent one to outsiders.
The full-contact sport, which sees amateur and professional fighters duke it out in a caged ring, now rivals boxing and professional wrestling in live event and pay-per-view revenue.
The sport serves as a dramatic setting for the gritty family drama Kingdom, produced by America's DirectTV service.
"I have done a full 180-degree (turn) on MMA and UFC (Ultimate Fighting Championship)," actor Jonathan Tucker tells APN.
"It was a sport I thought was utterly depraved and anybody who was interested in it was not somebody I was keen to spend time with. Now I'm completely and utterly obsessed with all things fighting."
Tucker is best known for his starring role in Parenthood and has made a stunning physical transformation to play Jay Kulina, a former fighter and drug addict whose father Alvey (Frank Grillo) runs a small MMA gym in Venice, California.
"It's a family drama," he says.
"I can't imagine a lot of people were keen on humanising the Italian American mafia (in The Sopranos) or thought we could make a fully-realised character out of Tony Soprano, or that you could fall in love with a drug-making tag team duo in Breaking Bad.
"A show and a role like this is what every actor hopes to have at some point in their career."
Tucker is almost unrecognisable compared to his clean-cut character Bob Little from Parenthood. Despite Jay's addiction issues, he still has the slim yet muscular frame of a fighter.
He puts aside his differences with his father to support his younger brother Nate's (Nick Jonas) debut fight.
"Jay is one of the creepiest spirits I've ever danced with before," he says.
"Anybody who has experienced addiction or dealt with an addict knows every day is a new day and every day is a day working on your sobriety. There are falls but the hope is they allow you, like a baby, to stand up and every time you stand up your legs get stronger."
Kingdom debuts tomorrow at 9.30pm on Foxtel's FX channel.
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