Although Leroy Jethro Gibbs got to see how his life could have played out differently on the landmark 200th episode of NCIS, he decided he wouldn't have it any other way.

NCIS celebrates 200 episodes with an emotional "what if?" story

After being fired at while enjoying his morning cup of coffee at a diner, Gibbs (Mark Harmon

) was led by the ghosts of Mike Franks (Muse Watson), Riley McCallister (Michael O'Neill) and Gibbs' wife Shannon (Darby Stanchfield) to some of the defining moments of Gibbs' life and the series. What if Gibbs had stopped a sniper from killing agent Kate Todd (Sasha Alexander)? What if Gibbs hadn't killed the man who murdered his family? And what if Gibbs hadn't been an NCIS agent at all?In the end, truth was better than fiction for Gibbs. We chatted with executive producer Gary Glasberg about creating this one-of-a-kind hour, the technical wizardry used to recreate certain scenes, and the first appearance of Gibbs' mother (Clare Carey). Plus: How will this experience change Gibbs' outlook on the future?
Congratulations on reaching this milestone! What sort of feedback have you gotten today?

Gary Glasberg:
So far what I've seen and heard has been very positive. This episode was really an homage to the fans, and the goal was to make people think a little bit, not only about decisions in their own lives, but in Gibbs' life as well and where [his decisions] have taken him over nine seasons. It's a challenge to pack nine seasons into 42 minutes. I hope I accomplished it.

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How did you go about deciding which specific moments you wanted to revisit in this episode?

Glasberg: There were lots of moments that our other characters were the deciding factors in. But because of the standpoint we took in this show it was really about Gibbs. That was something that helped us separate one moment from another. These are the moments that we thought if Gibbs had handled himself differently, how would it have worked out?

These are also the moments that Gibbs perhaps still feels guilty about?
Glasberg: A big part of Gibbs and any sort of hero character is what they're carrying around inside and the weight that's on those shoulders. A big part of what drives Leroy Jethro Gibbs is these decisions that he's made. Whether he was right or wrong, in his mind, he acted the way he needed to in the moment. I think we all look back on things that we may have wanted to do differently, and this is what he's been carrying around.

One of the biggest moments had to be the reveal of Gibbs' mother.
Glasberg: This was a very unique opportunity to meet this woman who was hugely influential in his life that he lost at a very young age. It was an opportunity to reconnect with her and see what kind of woman she was and what kind of effect she would have had. I don't know when this kind of opportunity may come up again, but we wanted to seize it and take advantage of it.

Do you think we will ever see her again?
Glasberg: If something else arises, I'm not going to say no. We'll see what the writers come up with and if we feel like it's a direction we want to go in again. Clare is a fantastic actress and she totally delivered for us. It's nice to know that we can add her to the arsenal.

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You obviously used lots of familiar faces in this episode. How did you decide which characters would get a scene versus a knowing glance?

Glasberg: That was part of the fun. For months now, we've been trying to determine how we could pull this off —who would speak and who wouldn't speak and who we could get to come and play with us. It's tricky filming an episode around the holidays because you never know if people are going to be in town or if we can get them. So you have instances where you have the actor walk through the diner ... or you have some situations where we optically re-created it. It was a big challenge, but it was fun and we were happy to be able to do both.

How much trickery was going on in some of those optically re-created scenes?

Glasberg: My hat is off to my post-production team because they have spent weeks and weeks and weeks doing those sequences. It's very tricky, whether it was Jenny Shepard (Lauren Holly) sitting in that booth for the brief moment that she was, or Sasha Alexander, who was out of the country at the time. We took that image from the episode with the plague, and totally recut it. We went back into dailies and made that work.

And Kate married and had a baby with Tony (Michael Weatherly)! I guess "Gibbs' rules" don't apply in fantasyland.
Glasberg: I'd like to think that in our instance, you can bend the rules a little bit. In truth, the way we laid it out in this story, Tony and Kate get together and Gibbs, feeling the pressure of what happened to his wife and child, ended up leaving the agency entirely. So the rules don't necessarily apply because he removed himself from the scenario. Believe me, hours and hours were spent talking through all this, and whether it all completely fits or not, we were pretty careful about trying to make sure everything clicked.

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And yet you still managed to have a crime story.

Glasberg: That was the fun part. I didn't want to deliver an episode that didn't have a crime to it and was just made up of the "what if" moments. Compared to many of our more complex [mysteries], there's a very simple story there about a father's desperation and what he's willing to do to provide for his son. There are absolutely overlaps of decision-making and loss that parallel [Gibbs' story]. The goal was at the end to have one story dovetail into the other.

McGee (Sean Murray) also faced a big decision: whether or not to leave his team for a promotion in Japan.
I wanted to give McGee the opportunity to make some tough decisions as well. This was an opportunity to do something professionally that he probably would have really enjoyed, but he wasn't ready to leave his family.

Even in some of the darker "what if" moments, Gibbs had the support of his team. Was that one of the take-aways you wanted?
Yeah. I like to think that bond is stronger than ever. None of these things would have come together had he not decided to join NCIS and ultimately become an NCIS agent. At the end of the day, he has to appreciate at least what got him here. And even though he's experienced tremendous loss and pain along the way, [the team] is his family now.

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Why did you want to have several characters tell Gibbs that life "doesn't work that way" during these sequences?
I think it's really about that, unfortunately, the world doesn't always allow us to steer things in the direction we want. Things unfold and happen that are sometimes difficult. And we have to accept them and move on.

So, will we see Gibbs moving on with a changed perspective?
I don't know if Gibbs will ever really be able to let go of all of the demons. But I think as he recognizes the truths of what he's been through and the complexities of what he's experienced that he will be able to move forward a little bit. It's two steps back and one big step forward. Hopefully, now that he's gone through this, it will have an impact as he looks to the future.

What did you think of NCIS' 200th episode?