NCIS Star Diona Reasonover Talks Kasie's 'Beautiful' Showcase Episode And Abby's Lab Legacy, Teases Finale's 'Huge Cliffhangers'

Warning: This post contains spoilers for Tuesday's "NCIS."

This week on "NCIS," Kasie Hines finally got out of the lab.

In the second part of a two-parter with LL COOL J returning as Sam Hanna, Kasie realized that last week's deadly sabotage was all to steal Edna, a program she'd been developing in secret to use fingerprints to identify distinct genetic markers in a suspect. The program was worth millions... and the thieves used it to frame Kasie for murder. To rebuild the program from scratch, Kasie had to reconnect with an ex from college, Joanna, and the wounds from their breakup were still fresh. But Sam helped Kasie get Edna back and prove her innocence — and Kasie moved Edna to the trash bin to prevent it from ever being misused again.

It's the most action Kasie has seen in a long time, so TVLine reached out to Diona Reasonover (who's played Kasie since Season 15) to break down the episode and the window it gave us into Kasie's inner life. Read on to get her thoughts on Kasie's bond with Sam — maybe an "NCIS: New York" guest spot is in her future? — and how Kasie stacks up against the original "NCIS" lab nerd Abby Sciuto. Plus, she drops a few hints about the "huge cliffhangers" in store for the May 12 season finale.

TVLINE | We haven't seen many episodes where Kasie gets out of the lab and gets this kind of showcase. What was your reaction when you read the script?
I started sweating immediately. I started being like, "I don't know if I can do this." I went to Marco [Schnabel], the writer, and I was like, "I don't know, maybe make it all Knight. Make it all Jess Knight." [Laughs] But he is such a good writer. Marco, I thought, wrote such a beautiful, cool episode. And more importantly, it felt like the second part of another episode that he wrote, one of my favorite Kasie episodes, "Lifeline" [from Season 21]. In that, Kasie talked a lot about how she feels like she's the reason that she doesn't have a relationship, like she's always the common denominator. So her addressing that with somebody that she was in a relationship with, this felt like the perfect companion piece to that.

TVLINE | Kasie developed this reverse genetic identifying program called Edna that's worth tens of millions of dollars, but she never told any of her NCIS colleagues about it. Why do you think she kept this a secret?
You remember two seasons ago when people were like, "Hey Kasie, we had to go to your apartment. Turns out your apartment's a mess, and you didn't tell any of us"? Kasie's constantly not telling people things. She has a real fear of vulnerability that I think she's finally addressing. I really want to see an episode where she's basically like Jim Carrey from "Yes Man," where she just tells everybody everything that's going on with her, no matter what, just to try it out.

TVLINE | We also learned that Kasie had a relationship with this girl from college, Joanna, that ended badly. What kind of insight into Kasie's personality do you think we get as viewers from learning about that breakup?
You know, we don't get to see Kasie argue with someone very much. Normally, she's just really positive, just sharing information. So to see her be so stubborn and sort of unable to hear the other side of it, I think it's a real surprise for people. I think that we get to see just how scared she is, because that freezing up, that comes from tension, that comes from being scared. And I think people will be surprised to know that Kasie was so self-conscious, because she's a very confident person most of the time. I was surprised to learn it.

TVLINE | Sam Hanna was really the one who gave Kasie the inspiration she needed to keep Edna out of the wrong hands. Do you feel like they have a special kinship, even though they haven't really spent that much time together?
LL COOL J is so charismatic and easy to talk to in real life, so he kind of just brings so much of that trust to set with the character, with his demeanor, that I'm not shocked at all. I mean, if LL COOL J came into your room right now, sat down, and said, "So tell me about you," wouldn't you open up?

TVLINE | Kasie ended up getting rid of Edna because it's just too dangerous. But was there a tiny part of Kasie that kind of wanted to sell Edna and cash out? I mean, we're talking about big money here!
Yeah, no, I think it just took one being framed for murder for her to say, "I'm good." Everybody talks about the money, but you know, you might waste all that money on a good lawyer.

TVLINE | So Sam Hanna is moving to New York for "NCIS: New York," and we know now that Joanna lives in upstate New York. Does this mean we might see Kasie in the Big Apple in this new spin-off?
We're on the same wavelength. That's what I'm hoping for. That's what I'm pitching. That's what I'm going to the network with. I've also gone to them with several travel itineraries. But they won't get back to me. [Laughs]

TVLINE | Kasie replaced Pauley Perrette's Abby as the show's resident lab rat, and Abby was an "NCIS" icon. But you're about to enter your 10th season on "NCIS," which is approaching how long Abby was on. Do you feel like Kasie has earned a place alongside Abby in "NCIS" history by now, or do you still feel like the new kid in class?
It's very funny for it to be that long, and people are still like, "So you're a new person!" I mean, when I look at sort of the Mount Rushmore of "NCIS" characters, I know that I'm on my mom's version of it. [Laughs] But I think the ones that really made their mark are obviously Abby, Gibbs, Ziva, and Tony. I'm really so proud of this new class of "NCIS" people, and I think that we're continuously stepping up, continuously pushing the show and storylines forward. And I also think it's OK that when you see Abby's pigtails, you know who that is.

TVLINE | I loved seeing Kasie trying on Abby's old clothes in the 500th episode. That was such a great nod to her. So she still holds Abby in high regard?
Yes, I think very much so. That was so cool for me, because I was calling myself Goth when I was in college when I was wearing, like, khakis. My parents wouldn't buy me any black clothes. So for me, that was like a dream come true.

TVLINE | Even today, it's still pretty rare to see a Black woman playing the science nerd on a show like this. Do you hear from young Black girls who look up to Kasie and are inspired to pursue science because of her?
I do, and it's a total full-circle moment, because when I was doing my research for the show, I saw so many young girls saying how much they looked up to Abby. Pauley was on the screen for so long that people literally went through college and became a scientist because of her. So now that's started happening to me, where people are like, "I applied to college. I'm so excited. I hope I get in." I'm like, "I hope you do too!" It means a lot to me, and I think it means a lot to a lot of people out there, which I'm so incredibly grateful for.

TVLINE | So what's next for Kasie and the team? Can you tease anything about the season finale?
Huge season finale. Huge cliffhangers. The season finale is really cool because we have a bunch of guest stars coming back. But we do have some returning faces. We have Harriet Parker coming back, to avenge Vance's death towards the end of the season. And then we have some people that I know I'm not supposed to say their names, but I think the audience will be satisfied and shocked, and they will be primed and ready for Season 24.

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