Is NCIS' Tony DiNozzo really the best man to carry out the Navy secretary's search for a mole? With all possible respect to DiNozzo (Michael Weatherly) as an agent, isn't he a little too goofy for super-secret spy work?

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"You ask the question that's on everyone's mind," Weatherly tells with a laugh. "When Tony gets to play James Bond, he takes it very seriously. DiNozzo, despite his goofiness, is the soul of discretion. I believe he possesses a good capacity for secrets. One of the reasons for that is that no one would ever think that he could keep a secret. It's kind of like hiding in plain sight by giving him the mission."But the secret won't stay hidden for long. In fact, in Season 9's premiere (Tuesday, 8/7c, CBS) Tony's investigation will culminate with a fellow NCIS agent being killed. Viewers will retrace Tony's steps through flashbacks, but Weatherly also promises a deeper dive into Tony's mind when NCIS shrink Cranston (Wendy Makkena

) returns."There's some sort of a psychological poking around into DiNozzo's brain," Weatherly says. "Ultimately, I guess I learned more about my character, more about his childhood, and that's always helpful and intriguing. ... Tony is a very compartmentalized dude. That's how he protects himself, and it's clearly how he protected himself since he was a kid."And some of those revelations may pay off when DiNozzo's father (Robert Wagner) returns to the show for this season's Christmas episode. "I'm sure there will be all the style, the panache, and glamour that Mr. Wagner always brings with him ... but I have a feeling that there's a good bit of edge that we'll have in this one," Weatherly teases.

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However, the mole hunt may have a greater impact on DiNozzo's relationship with his surrogate father, Gibbs (Mark Harmon). "DiNozzo's being tasked by someone outside of the immediate chain of command, meaning Gibbs," Weatherly says. "It's very unnerving. There's some nice drama with Gibbs and I think in a way it pieces together some of the stuff that was happening at the end of last year between DiNozzo and Gibbs."But Gibbs isn't the only one miffed that SECNAV (Matt Craven) is messing with a member of his team. Vance (Rocky Carroll) is also out of the loop for the first time, which executive producer Gary Glasberg says will play out in a number of stories this season."It adds a whole new dynamic to the way that the team functions," Glasberg says. "I wanted to focus on stories that actually pull our team together and have them take on a lot of what they're facing as a unit. As they evolve as co-workers, my goal is to continue for them to have an appreciation for the responsibilities that they each have. I think this is really going to bind a lot of them together."While we can't be certain who the mole is, there's certainly some suspicion surrounding DiNozzo's ex, E.J. Barrett (Sarah Jane Morris) — considering that the last time we saw her, she was pulling a microchip out of her dead teammate's arm. "There's a new wrinkle in their relationship, and I would say it is somewhat troubling," Weatherly teases. "I think Tony questions a lot of things about her and I don't think there's any going back to their initial blinky-blinky, lovey-dovey plot."

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Does that clear the way for Tony to get cozier with teammate Ziva (Cote de Pablo)? Not so fast. "Due to somewhat traumatic events that kick off the story, he ultimately has to lean on himself," Weatherly says. But he also suggests that Tony's time in therapy may open that possibility down the road."All of the goofiness and the sense of humor and the deflection is clearly covering something nasty eating away at him inside," Weatherly says. "I think that this should take us one step closer to maybe understanding an essential core truth... about what makes Tony tick. I think that you have to do that work alone sometimes. But it might make him more able down the road more able to approach a relationship with Ziva."And similarly, Weatherly says despite being handed a secret mission, DiNozzo knows he's not yet ready to leave Gibbs' nest. "That's far off in his mind," Weatherly says. "He still knows that he needs the guidance. He needs to find that missing link and I think that he knows instinctively that Gibbs is the one who can show him that. It's why he's there."NCIS premieres Tuesday at 8/7c on CBS.