NCIS: Los Angeles: Nate Is Back --- And This Time It's Personal

Ever since Peter Cambor became a recurring cast member on NCIS: Los Angeles, the return visits of operational psychologist Nate Getz have been rather illuminating.

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While last season revealed Nate to have become exceedingly more skilled in hand-to-hand combat than we ever imagined, this time around, the case is personal, dealing with matters of the mind — and, more importantly, the heart. When the team's investigation of a Marine's death leads them to the morgue, the agents begin to question whether the coroner, Nate's former flirty friend Rose (Kathleen Rose Perkins), is hiding information."Nate kind of has a thing for Rose and Rose kind of has a thing for Nate," Cambor, who now stars on TBS' Wedding Band, tells TVGuide.com. "Hetty [Linda Hunt] has very specific designs as to why they need Nate. It's because of this relationship. They're exploiting it to get into the case in a more specific way."Although Cambor says Rose is surprised to see Nate sitting across the table from her, Nate is used to picking the brains of those closest to him. But now, there is more at stake. "It was unlike any interrogation I've ever done on the show before," Cambor says. "Nate's kind of a shy guy, but it seems he's finally getting to make some headway with this person that he's really, really interested in. All of a sudden he has to give her the third degree. It's the one time he doesn't want to be there. He's really doing this against his will."

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But like a good agent, Nate follows his orders, which ultimately find him going undercover with Hetty. "I may or may not be playing her son," Cambor says with a laugh. "The undercover scenes almost play like a Wes Anderson movie. It's so surreal."Cambor says its an apt situation, given Hetty's mother-figure role to many of the NCIS agents. "I really think she's a teacher, like a sensei," Cambor says. "It's like Mr. Miyagi and Daniel LaRusso in The Karate Kid. I feel like every episode, Nate is like, 'Why am I doing all of this?' Of course, at the end of the movie, Daniel's a great fighter."Indeed, Cambor believes Hetty is constantly training Nate for some unknown future goal. "What Nate has to do is hone his intellect," he says. "That's something he shares with Hetty. She's not physically imposing, but she's incredibly intelligent. I think part of him being sent away has to do with him getting tougher, but ultimately ... he needs to become a better mental and intellectual and emotional warrior. Hetty's always testing everyone, but this is really where he will become invaluable."

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But like all tests in life, it's not easy. In fact, because of the personal nature of this case, Nate will begin to question his choices. "This is the first time Nate is psychologically put on that tightrope," Cambor says. "If he's keeping an eye on everyone else, who's keeping an eye on him? He doesn't know if he can do this."Fortunately, Nate finds his answers by the end of the episode — even if that means losing Rose. "He's confirming that this is his life — beyond anything else, this [work] really does precedence," Cambor says. "It's a wake-up call for him about how important this is to him. Hetty's really putting him through the gauntlet and as hard as it is, it's right for him. He's in the exact right place."NCIS: Los Angeles airs Tuesdays at 9/8c on CBS.