What Mark Harmon Told Diona Reasonover About Her First 'NCIS' Script

Diona Reasonover co-wrote the 'NCIS' Thanksgiving episode adding gallows humor for Kasie.

Diona Reasonover has been a member of the NCIS family, playing forensic scientist Kasie Hines since season 16 after recurring in three episodes the previous year, but tonight she adds a new credit to her NCIS resumé as the co-author of the “Turkey Trot” episode along with executive producer Scott Williams.

“I’m glad to say I actually came to them, and I said, ‘I have a great idea,’” Reasonover tells Parade in this exclusive interview, “and I listed my idea and they said, ‘Ooh, no.’ And then I gave them four more. I bothered Scott Williams, who wrote Kasie’s first episode, and I said, ‘I love your writing. I’d love to write with you if you’d let me.’ And he said, ‘Yeah, bring me ideas.’ And together we wove this idea of expanding Katrina Law’s (Jessica Knight) family together.”

In the “Turkey Trot” episode, Kasie joins Knight for Thanksgiving lunch at Knight’s sister Robin’s (Lilan Bowden) Airbnb after an unknown shooter causes chaos at an annual Thanksgiving 5K and it appears that someone is threatening the life of Navy Rear Admiral Martha Stock (Gillian I. White). But because it’s a holiday and the NCIS team is having trouble getting a hold of anyone to gather evidence, Parker (Gary Cole) excuses Knight and Kasie to go break bread with Robin.

Initially, the idea that Reasonover had was that it was going to be Knight and Jimmy Palmer (Brian Dietzen) going to lunch at Robin’s, but there was already the “Leave No Trace” Knight and Palmer episode in the works, the one where Knight’s ex-boyfriend returns and hopes to win her back.

Related: There's Romance in the Air on NCIS! Brian Dietzen on the Jimmy Palmer-Jessica Knight Affair!

“At that time, that was still very much in development, and we weren’t sure where that was going to go,” Reasonover continues. “So, Scott was like, ‘We’ve got to do someone other than Knight and Jimmy.’ And I literally begged him. I said, ‘Please not Kasie, she’s been through so much.’ And he said, ‘Baby, it’s Kasie or it’s nobody.’ So here we are.”

Without giving too much away—no spoilers here—this will be the third time that Kasie will be held hostage, which is why Reasonover told Williams she’d been through so much. Although, this time around, due to the dysfunctional family dynamics between Knight and her sister, Kasie has been hitting the wine to help her get through the lunch.

“Once we decided to jump in and do Kasie and Knight, we didn’t want to just have it be a repeat of the same emotional beats, so we gave her a little bit of a more comedic twist with this one,” Reasonover says. “I wouldn’t say she’s used to it, but she’s got this sort of grim humor about it at this point because it is getting a little ridiculous. But she’s not going anywhere, I’ll tell you that.”

What made writing her first NCIS episode even more special is that Mark Harmon (Leroy Jethro Gibbs) came to the set one day while they were filming and complimented her on her writing debut.

“Mark came up to tell me that he loved the script,” Reasonover relates. “I don’t know that that’s the reason he drove up to where we were, so I’m going to say it was the reason. He probably had other people to talk to. But he literally did, I got to hug him and talk to him and catch up, that was great. So, Mark is definitely still present, he gets every script, he’s still an EP, and he still very much acts like one.”

Related: NCIS Star Diona Reasonover on Who in the Cast May Surprise You and on Giving Back Through Urban Solutions

During our chat, Reasonover, whose character Kasie brings a mac and cheese side dish to the Thanksgiving lunch, talks about her family recipe; she shares her most memorable episode; and what she would like to do with Brian Dietzen.

Kasie makes mac and cheese as her contribution to the Thanksgiving meal. Since you wrote this, I have to ask, is that a favorite of yours? Do you have a family recipe for mac and cheese?

Oh yes, I was so hoping that someone would ask me about this. Absolutely. My dad is from Tennessee, so I make a classic Southern mac and cheese. It definitely involves eggs; it’s a lot more custardy than Kraft Mac & Cheese. I have in the past, per my wife’s request, made a creamier mac and cheese, but gosh darn it, I’m the cook and I will make the decision on the type of mac and cheese that will be served on Thanksgiving. I was very tempted to make my family’s mac and cheese and have it in the container, but that would be a waste of delicious mac and cheese and I won’t do it.

Well, I love mac and cheese, and I thought, “Wow, that’s a small casserole. She needed to have a bigger one.”

You know what? Props felt the same way as you. Props originally gave me this giant 9-inch x 13-inch casserole dish filled with actual macaroni and cheese. And I was like, “Guys, this is way too heavy.” It was like a brick. I was like, “No, I still have to do this scene, this walk and talk scene 14 more times, you’ve got to give me a smaller dish.”

What is the process like to cowrite? Are you in the same room? Do you share computer screens from different locations?

For me and Scott, it’s a lot of talking, which is really nice because we got to talk about our families, we got to talk about our family traditions, funny things that have happened to us on Thanksgiving. And we batted around ideas verbally and then did a little card outline. But then we actually separated, and we each wrote disparate storylines.

I know when Brian Dietzen, who wrote “The Helpers” with Scott, and I don’t want to put words in his mouth, but I’m pretty sure it was like, “You write the first half, I’ll write the second half.” We had one of us write the Airbnb storyline and the other one wrote all the squad room and explosion scenes. And then we wove them together, and the person who had worked on one storyline switched over to the other and vice versa. It was really fun.

It was so great because Kasie’s just a really upbeat character. So, I think one of my favorite things, even though it’s not what I intended, was to explore this gallows humor that she had about the situation at that point.

Can I give a shoutout to the director, by the way? This episode was directed by Lionel Coleman. He’s never directed for NCIS O.G. before, he’s done L.A. He was so phenomenal to work with. Really there were times when I wasn’t on camera that I was watching and I wanted to get in there and be like, “Oh wait, no, I meant this line to sound more like this.”

But he was really gentle with the actors and patient, and really made sure to protect all the performances and draw out these really incredible performances. That watch scene with Knight’s character, I was literally in tears. There’s a moment where it shows me in tears and it’s literally me crying, it’s not acting. I’m sitting there just sobbing watching her do the scene. I want to give a real shoutout to him because he was the key that made this episode what it needed to be.

Do you want to direct? Daniela Ruah directs L.A.

I’m pretty happy if Lionel keeps directing. I’ll leave that to Lionel and Rocky Carroll. I want to keep writing though. I hope I get to write more; I love that. I don’t like answering questions and the director’s chair is too high. I think it would be fun if Brian and I wrote one. I’m like, “Oh, Jimmy and Kasie do a TikTok dance and solve a crime,” yes please.

NCIS isn’t the same show that you joined. There have been cast changes. Talk about how it feels different now that Mark Harmon is gone, and Gary Cole is leading the team.

I miss those Gibbs scenes so dearly. And Parker is a completely different ball of wax. I love that we’re starting to explore his character, finding the edges on Parker. Gary is just absolutely a joy to work with and he’s so easy to work with, it’s so wild. It’s really an embarrassment of riches.

Related: Find Out the Secret Past Gary Cole's NCIS Character Alden Parker Has Been Hiding

Despite Mark Harmon’s exit, the show is still doing really well in the ratings. What do you think it is about the show that it manages to keep the audience watching?

I had the same worry when Mark left. I was like, “Is this show going to keep going?” I think it is that legacy that Mark built, Mark and Gibbs, and all the writers built this kind of family. That’s really what it is. They built a family and we’re lucky in that you love more than one character, so you want to continue seeing this family interact.

And that’s really what this is always about. It’s not about the cases. I know people probably say that. It’s really not about the cases, it’s about the interactions that these characters have. And I think you have to be really compelling. I was not watching the show from day one, but I look at how much Jimmy’s character has grown in the five years that I’ve been there. I look at how much he’s been through. I look at how much Sean Murray’s character (Timothy McGee) has been through, everybody. And I have to imagine that that’s pretty compelling and you want to keep watching these characters.

Let’s talk about what I consider your most memorable episode, the one where Kasie and Jimmy were quarantined in the lab and they’re dying. Is that the most memorable to you also? And how hard was it to play? There’s that emotional phone call to your family. There’s so much going on in that episode.

That one was pretty memorable for a couple reasons. One, I was just so absolutely proud of Brian. It’s always so much fun to have scenes with him. He and Scott let me just absolutely go wild in that scene. It wasn’t my most memorable even though that episode holds a near and dear place in my heart, but I think it’s really when Kasie decided to be here.

The most memorable episode, if I’m being honest, not for lack of love, is there was another episode where Kasie is walking through a pond. I don’t know why but the writers thought it would be funny to get Kasie in the field. And they put me, Diona, in a pond out in Disney Ranch and I cannot swim, and I was terrified.

I got stuck in the mud for real. They put this platform in the pond for me because the pond was really deep. And they’re like, “OK, just don’t step off the platform.” I’m like, “Where’s the edge?” And my whole boot got stuck down and I could not move. And I was just stuck in the middle of this pond. I was like, “Am I stepping off? Has something reached up and grabbed me? Is the lake monster here?” That’s for me, at least for filming purposes, my most memorable.

NCIS airs Monday nights at 9 p.m. ET/PT on CBS.

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