Hawaii Five-0

McGarrett's in prison for murder. Kono's been stripped of her badge. Chin Ho has rejoined the Hawaii Police Department that once betrayed him. The governor is dead. Where does Hawaii Five-0 go from here?

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"It's going to be a very different Five-0," executive producer Peter M. Lenkov says of the new season, which premieres Monday at 10/9c on CBS. "The most important thing is that they need to get back together. These people need each other. It's going to be fun seeing them put the pieces back together."

Helping to kick-start that effort is Lt. Cmdr. Joe White (Lost's Terry O'Quinn), who comes to Hawaii on a mission to exonerate McGarrett (Alex O'Loughlin). "He was a mentor. He was his commanding officer," Lenkov says. "Given the kind of character that McGarrett is, imagine the guy who trained him." Adds O'Loughlin: "[He] is the closest thing McGarrett has to a father. To have him around is something that's very special [for McGarrett], although he'd probably never admit it."

But even with McGarrett's name cleared, will he be able to depend on his team to have his back? Lest we forget, it was Chin Ho (Daniel Dae Kim) who arrested McGarrett in the season finale. "They're a family... but there may still be a little bit of mistrust," Lenkov says.

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"The emphasis is more on how the team stays together, whether it can stay together," Kim adds. "There are new, outside forces that are introduced that are going to be causing some internal tension."

One of those forces is guest star Tom Sizemore's Capt. Vincent Fryer, a Detroit homicide cop who is now running HPD's internal affairs division. He'll be keeping his eye on Kono (Grace Park), who is still suspected of stealing the money from the evidence locker. Another is Dr. Akina (Autumn Reeser), a maritime museum curator who will complicate the relationship between Danny (Scott Caan) and his ex-wife, who offered Danny a second chance in the finale.

Then, there is Lt. Gov. Sam Denning (Richard T. Jones), who's had to clean up the mess left by Gov. Jameson's murder and her connections to Wo Fat (Mark Dacascos) since succeeding Jameson as governor. "He's done much damage control coming in," Lenkov says. "But he's also a guy that knows that Five-0 can't act the same way that they acted last season. They can't just have immunity and means. That was given to them by a governor who had an agenda. He's going to keep them on a shorter leash; that's for sure."

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And we all know how much McGarrett likes being told what to do. "McGarrett has all due respect for [Denning]," O'Loughlin says. "He's a pretty forthright guy and he's pretty tied to his methods, [but] his methods are a little unconventional. [McGarrett's] primary concerns are that this guy is not going to get in the way of him doing his job."

McGarrett's feathers will be ruffled, however, by one of Denning's first acts: putting a new member on the Five-0 team. Enter Lori Weston (Lauren German), a former homeland security officer who will be introduced in the season's second episode. "There's suspicion with any newcomer, especially if they come from another government agency and they're not picked by [McGarrett]," O'Loughlin says. "Anyone outside of the team that he hand-picked, he'll be a little dubious of. [But] she proves herself."

Might she prove herself to be more to McGarrett than just an asset in the field? "There were all of these reports that McGarrett gets a love interest, but she becomes a credible, viable, strong member of the team," Lenkov says. "She's beautiful, McGarrett's single and there is ultimately that possibility, but right now, she's just a member of the team. We'll just let nature take its course."

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Even with all the changes happening to the characters, Lenkov says the show itself hasn't changed. He promises the same action-packed hour that viewers experienced in the first season, and he says a new season-long mystery will be uncovered in the first episode.

"It's a really compelling mystery. I'm hoping it hooks people," Leknov says. "I actually think it's more meaty than the mystery last year ... Our goal is just to tell better stories and grow our characters and grow our family. And to keep a mystery alive."

Hawaii Five-0 premieres Monday at 10/9c on CBS.  

(Additional reporting by Hanh Nguyen.)