NCIS: Los Angeles Stars Tease 'Fans Will Feel Fulfilled' and 'Happy' with Series Finale

CBS

The stars of NCIS: Los Angeles are just as emotional about the series' upcoming finale as fans are.

As the first and longest-running NCIS spin-off approaches its May 14 curtain call, some of its biggest stars, including LL Cool J couldn't help but reflect on the show's 14-season run.

"You know, I mean, this is 14 years later," the 55-year-old rapper, who plays Senior Special Agent Sam Hanna, told PEOPLE exclusively during the show's wrap party on Friday. "Normally they'll be like, 'All right, that's an episode wrap,' but this was an episode wrap, a show wrap and a series wrap. It was big and felt big, but it felt like we accomplished something."

RELATED: NCIS: Los Angeles to End Series with Season 14, Finale to Air on May 14

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While he says there's a "melancholiness on some levels," LL Cool J, whose real name is James Todd Smith, says he feels good about the show's "huge accomplishment."

"It's like winning crazy Super Bowls or something," he added, explaining that he filmed the two-part series finale without reading the final script.

"I actually backed off it, you know what I'm saying?" the actor confessed to PEOPLE. "I played it scene by scene, and I let it surprise me a little bit."

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And according to costar Chris O'Donnell, some of those surprises include unexpected appearances during the finale.

"It wasn't what I expected, but I felt it was very appropriate," said the 52-year-old actor, who plays NCIS Special Agent G. Callen.

RELATED: Linda Hunt's Fan-Favorite Character Is Returning to NCIS: Los Angeles

Medalion Rahimi, who plays Special Agent Fatima Namazi, echoed similar feelings when speaking about the highly anticipated farewell for the spin-off, which premiered in 2009 and has run for more than 300 episodes.

"I think the fans are going to be be really happy because we do close a lot of storylines, we bring some closure to a lot of the characters, and I think there won't be anything left unfinished or feeling unfinished," shared Rahimi, 30.

Eric Christian Olsen, who plays lovable agent Marty Deeks, added that fans will "feel fulfilled by the end of these arcs."

"And I can speak for myself," he continued, "I think Deeks is searching for the family he didn't have — and he found love with Kensi [Daniela Ruah], he found parenthood with Rosa [Natalia Del Riego], he found a much more stable mom with Linda Hunt's Hetty, he found the brothers he never had with Sam and Callen, and peace at the end of that arc I think is really fulfilling for an actor to play — but also for the audience."

But Olsen, 45, didn't stop there, teasing: "And there's also some surprises coming. It's worth it."

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NCIS: Los Angeles airs Sundays at 9 p.m. ET on CBS.