TV shows are lucky if they’re able to last multiple seasons, let alone make it to air. NCIS has far exceeded those expectations, because not only is its 23rd season is still airing on the 2026 TV schedule, the popular CBS procedural will reach its 500th episode at the end of the month. However, CinemaBlend learned from Brian Dietzen, who’s been playing Jimmy Palmer since Season 1, that this milestone episode will have a much different feel compared to past ones.
He opened up about this when I spoke with him and Kasie Hines actress Diona Reasonover about their new podcast, NCIS: Partners & Probies, as well as what it was like reuniting with Emily Wickersham on the latest episode (which you can stream with a Paramount+ subscription). When I asked them what they’re most excited for NCIS fans to see in the 500th episode, Dietzen answered:
I would say that for each of our other 100th episodes, celebrations, the 100, 200, 300, 400, they’ve generally been retrospective; like look back and celebration shows of what it is. And this episode is not that. It’s very atypical. This is a very powerful kind of series-defining episode that’s gonna change the way NCIS operates from here on out. So it’s an event, and it’s one that I think if you miss it and you hear about it the next day, you’re going to be kicking yourself that you didn’t just get to see it with your own eyes first.
To paraphrase Leonardo DiCaprio in Django Unchained, the 500th episode of NCIS had my curiosity, now it has my attention. Like Brian Dietzen, these milestone episodes have been a good opportunity to look back on NCIS’s history, packing them with callbacks, special appearances, etc. The 500th episode, however, won’t do that, but instead deliver a story that sounds like it’ll shake up the show’s status quo in a huge way, going off what Brian Dietzen said.
There’s no plot synopsis yet for this episode, titled “All Good Things,” but it is worth mentioning that Brian Dietzen informed me last December that the budget cuts and incorporation of AI that the first half of NCIS Season 23 mentioned/explored would “fuel some pretty major storylines” in the second half of the season. That got me concerned about the show potentially paving the way for Sean Murray’s Timothy McGee to exit, and that concern grew in early February upon learning what the 499th episode will be about. Murray has been on NCIS even longer than Dietzen, debuting as McGee in its seventh episode. Him leaving would qualify as a major shakeup, and it’d be the highest-profile cast departure since Mark Harmon in early Season 19.
Or maybe I’m way off base, and what will make NCIS’s 500th episode “very atypical” has nothing to do with Sean Murray at all. I guess we’ll find out when “All Good Things” air on March 31. After that, there will be seven episodes left in Season 23, and then NCIS Season 24 will begin in the fall.