Across more than 1,000 episodes, the NCIS franchise has produced plenty of memorable TV couples — but few became fan favorites as naturally as Kensi Blye and Marty Deeks. Their chemistry felt inevitable from the moment they shared the screen, and their wedding episode still ranks among the franchise’s most beloved. Yet many may not realize that Kensi wasn’t always the playful, emotionally layered character we came to know. Her evolution began the moment Eric Christian Olsen joined the cast.
Before Olsen joined late in Season 1 (and became a series regular in Season 2), Daniela Ruah played Kensi as strictly no-nonsense — sharp, disciplined, and almost rigid. Speaking on Michael Weatherly and Cote de Pablo’s podcast Off Duty: An NCIS Rewatch, Ruah explained that in the early days, she took the directions “strong” and “smart” to mean her character had to be humorless and tightly wound:
“I thought I had to act with a stick up my ass. If she’s strong and she’s smart, she can’t be funny… And it affected every part of my body language. I thought tough meant one very specific thing.”
Kensi remained a formidable agent throughout the series, but something shifted once she began working opposite Olsen. With Deeks’ goofy charm and constant improvisation, Ruah suddenly had a scene partner who pushed her character in a new direction. Their dynamic — tough agent meets irreverent detective — was compelling on its own, but showrunner Shane Brennan saw a deeper opportunity.
Ruah recalled Brennan pulling her aside with a crucial note:
“If you react the way you’re reacting to Deeks, the audience isn’t going to like him — and you’re kind of an asshole. Even if you don’t like him to his face, if you crack a smile when he walks away, now the audience is with you, and they’re with him. And now we’re starting to create something.”
That “something” became Densi — one of the most iconic pairings in the NCIS universe. Kensi softened, Deeks matured, and their push-and-pull partnership evolved into a slow-burn romance that fans championed for years. The shift didn’t just change Kensi — it changed the trajectory of the series.
And the off-screen story is just as charming: Ruah eventually married Eric Christian Olsen’s brother and stunt double, David Paul Olsen. Talk about chemistry making an impact beyond the show.
Looking back, it’s hard to imagine NCIS: LA without the banter, the emotional growth, and the steady buildup that defined Kensi and Deeks’ relationship. Without Brennan’s note — and without Olsen’s comedic, improvisational energy — the characters may never have connected, and some of the show’s most memorable moments might never have happened. Their wedding, Kensi’s pregnancy reveal in the finale, the many heartfelt scenes in between — all hinged on that early shift in character direction.
Though NCIS: LA has ended, its legacy continues across the franchise. LL Cool J appeared on NCIS: Hawai’i before its cancellation, and Daniela Ruah returned for the milestone 1,000th NCIS episode, also stepping behind the camera to direct. Whether more LA cast members will appear remains a mystery, but for now, fans can look forward to the flagship show’s return this fall.
