Hawaii Five-0 Hawaii Five-0

Off the coast of Oahu, Alex O'Loughlin, the trim, toned and tattooed star of CBS' Hawaii Five-0 reboot, is chopping through the waves like the former Navy SEAL he's been hired to play. His perfectly sculpted six pack glistens as he emerges on the shore wearing nothing but taut navy trunks. "I think we just shot what is going to be the most downloaded scene of Hawaii Five-0," executive producer Peter Lenkov calls out to his crew. "It sort of makes everything I do from here on moot."

You don't need a coconut to hit you on the head to figure out this is not your father's Hawaii Five-0. It's younger, naughtier and definitely more action-packed. Even the core characters — including O'Loughlin's Steve McGarrett — have been reimagined.

Lenkov, who'd overseen CSI: NY and 24, partnered with Alias and Fringe producers Alex Kurtzman and Roberto Orci, hoping they could do for the origins of McGarrett, Danny "Danno" Williams, Chin Ho Kelly and Kono Kalakaua what they did for Kirk and Spock in their 2009 Star Trek prequel.

Together, they reshaped McGarrett as a mercenary heading up an elite task force — a man not above implementing torture to extract the truth. "That messy boy stuff is what I like most," says O'Loughlin. "There are definitely Jack Bauer elements to my Steve McGarrett. He's not averse to methods others would be jailed for. I did a scene yesterday where I'm hanging a guy by his ankles 36 stories above Waikiki."

Scott Caan plays McGarrett's partner, Danny, a by-the-book New Jersey cop transplanted to Honolulu to be closer to his remarried ex-wife and daughter. "Our characters are set up to butt heads," says Caan of the new partners. "But we're alike in a lot of ways." So are the actors—who happen to have been born within hours of each other. Just a few days into production on the second episode, it's clear they've developed a tight brotherhood. Between takes, they kick around a ball with Caan's constant on-set companion, a Blue Heeler named Dot. "Alex thinks Dot's Australian," cracks Caan, showing equal affection toward O'Loughlin's son, Saxon, visiting from Australia for a few days. Says O'Loughlin: "You just hit it off with some people. And we did."

The other half of the Hawaii force is made up of two seasoned sci-fi vets — Lost alum Daniel Dae Kim, as disgraced cop Chin Ho Kelly, and Battlestar Galactica grad Grace Park as his cousin, badass surfer chick Kona Kalakaua. Enrolled in surfing school, Park's been pounded by waves and scraped by coral. Even more intense are the high-impact fight scenes like today's, in which Park is being strangled, slammed against a bookcase and thrown into a swimming pool with a blow to the face by a heavy bamboo pole. A good sport, Park quips, "I like the girl-on-girl action stuff."

For more with the cast of Hawaii Five-0, pick up this week's issue of TV Guide Magazine, on newsstands Thursday!

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