Mark Harmon, Michael Weatherly Mark Harmon, Michael Weatherly

As NCIS chugs into its 12th season Tuesday (8/7c, CBS), creator Gary Glasberg says he's taking a back-to-basics approach for the upcoming year. After so many major event episodes last season — the departure of Ziva (Cote de Pablo), the introduction of Bishop (Emily Wickersham), the NCIS: New Orleans backdoor pilot, and a tribute episode to Ralph Waite — Glasberg says he's excited to be entering a more character-driven run.

"Season 12 is all about bringing the team together and sort of keeping the family going, and really emphasizing the group," Glasberg — who's also serving as showrunner on NCIS: New Orleans now — tells TVGuide.com. "We made a deliberate decision at the end of [Season] 11 to really do that."

With no cliff-hanger to resolve, NCIS gets off to a fresh start on Tuesday's season premiere, which finds Gibbs (Mark Harmon) and McGee (Sean Murray) heading to Russia to escort an NCIS computer engineer home safely. But they quickly find themselves the targets of a local mercenary group, putting both their lives and classified intel at risk.

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What else can fans expect from Season 12? And will Ziva ever be back? Here are seven teases from Glasberg and star Michael Weatherly.

1. Love is in the air: It looks like Dinozzo (Weatherly) is finally ready to put #Tiva behind him — and Weatherly, for one, couldn't be happier. "I think he's moved past the wounded bird [phase]," the actor says. "It's really exciting. I don't think I've been this excited since maybe Season 3. ... I think Season 12 is going to be a revelatory year. He's probably going to have more fun than he's ever had." Enter Leia Pendergast (Stephanie Jacobsen), a former U.S. marshal-turned-FBI Joint Terrorism Task Force leader who partners with Tony on a case ... and then in real life. Her introduction will happen around Episode 4." And as for "McGilah," though Delilah (Margo Harshman) may have accepted a job offer in Dubai, don't think that's going to put the kibosh on her and McGee's relationship for good, Glasberg cautions.

2. A new villain: The villain Gibbs and McGee encounter in their trip to Russia could have a very long reach. "[The premiere] introduces a character that'll carry through the rest of the season, and [will] even potentially overlap into the New Orleans show as well," Glasberg teases.

3. We meet Bishop's husband! Little is known about Ellie Bishop's personal life, other than the fact that she is married. In Season 12, viewers will finally get a glimpse of Bishop's husband, Jake, who works with the NSA. It's likely that he'll be introduced under the guise of helping out with a case or two, according to Glasberg. "It'll give us some more insight into her, into her background," he promises.

4. Abby meets her match? There will be plenty of crossover between NCIS and its newest sibling, NCIS: New Orleans — and one of the episodes will likely feature Abby (Pauley Perrette) meeting her NOLA counterpart, lab assistant Sebastian (Rob Kerkovich). "You will absolutely not only watch them interact for the first time, but there'll probably be multiple times after that as well," Glasberg promises.

5. A Duckling story: Episode 3 of the season (airing Oct. 7) will focus on Ducky's (David McCallum) backstory. Ducky and Bishop head to London to track down a childhood best friend of Ducky's who has a connection to a case. Adam Campbell will guest-star as a younger version of Ducky.

6. Gibbs gets multiple blasts from the past: The "one unnamed ex-wife of Gibbs" will probably make an appearance in one episode, Glasberg says. At the same time, Gibbs' father (Waite) may be gone, but he won't be forgotten. "There's no doubt that there's emotional resonance that he carries with him, and those moments will appear throughout the season," Glasberg says. "I don't think it'll affect him day to day at work necessarily, but there'll certainly be characters and moments that'll come up that'll be impacted by what he went through."

7. The return of Ziva? Tiva fans — all may not be lost. Both Glasberg and Weatherly say they'd welcome a story line that brings Cote de Pablo back to NCIS. With the actress having signed on to the upcoming miniseries The Dovekeepers, she'll remain in the CBS family — but will Ziva and Tony be reunited? "We didn't kill her," Glasberg hints. "So, Ziva's still out there and she's still alive. ... We'll just have to see what happens." Adds Weatherly: " I am sure they will see each other again, and I'm deeply fascinated by what kind of fireworks would result. I absolutely know that it would not be without some explosive quality."

NCIS returns Tuesday at 8/7c on CBS. What are you most looking forward to this season?

(Full disclosure: TVGuide.com is owned by CBS.)

Additional reporting by Adam Bryant

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