Nathan Fillion’s High Praise That Led to Major Part of ‘NCIS’ Joining Series

NCIS has been on so long — it’s going into its 24th season this fall on CBS — that other procedurals have come and gone in that time. But even with the high praise that this series received from those working on another procedural drama, executive producer and writer Scott Williams, who joined NCIS in Season 9 and remains there now, wasn’t planning for it to last this long. (He has over 50 written or teleplay by credits to his name for the series.)

While sitting down with NCIS: Partners & Probies podcast hosts Brian Dietzen and Diona Reasonover, Williams recalled how he’d been happily working on Castle when Gary Glasberg, NCIS‘ showrunner at the time, contacted him; they’d previously worked together on Bones.

“He says, ‘Don’t ask me how, but I’m running the number one show in the world, NCIS.  … I have a slot open next year if you want it.’ And I’m like, ‘Well, I am enjoying Castle, and I don’t know s**t about the Navy.’ And he’s like, ‘It’s a cop show with jokes and heart. It’s what we do,'” Williams shared, adding that his wheelhouse, and therefore NCIS, is “a lot of tongue-in-cheek stuff.”

He also revealed that Castle star Nathan Fillion encouraged him to take the job with NCIS: “He said, ‘Dude, I heard that’s the best gig in television. … I hear my actor friends go on there and they never want to leave. They can’t believe how nice everybody is.'” Dietzen chimed in with, “His buddy, Michael Weatherly, was on the show at the time, too.”

Fillion wasn’t the only one to tell Williams he’d “love it” on NCIS, and so he visited the set, spoke with Mark Harmon and others, and decided to take the job. But at the time, he wasn’t planning to be on the series for going into 16 seasons now.

“I joined in Season 9 thinking, what shows go beyond 10 years? So, even if this thing has another year or two left in it…” Williams admitted on the podcast. “A lot of my writer friends are quite envious of me because they know what a great gig it is, and if this is my last show or whatever, depending on where my career goes from here, what a great gig to go out on. Not that it’s going anywhere.”

NCIS, Season 24, Fall 2026, Tuesdays, 8/7c, CBS