"NCIS" has cast the first of two new characters joining the show at the end of this season. Sarah Clarke will play FBI agent Tess Monroemj, who has the potential to join Gibbs' team full-time starting in season 14.

The "24" alum will make her debut in the final two episodes of season 13, when her character transfers from New York City to D.C. to work with NCIS. The CBS drama is also expecting to introduce a young MI-6 agent named Clayton to the team at the same time, but have not announced his casting yet.

"We feel so fortunate to have Sarah Clarke joining us to play Tess," executive producer Gary Glasberg said. "I've been a fan of her's going back to '24' and more recently 'Bosch.' She's a gifted actress, a total pro, and we can't wait to introduce her to our 'NCIS' family and have some fun."

Glasberg has spent weeks searching for the perfect candidate to play Monroe, who is described as "quick-witted, sarcastic, shrew" and "two parts bulldog, one part kitten." Shortly before Clarke's casting, Glasberg said how excited he was that so many people want to a part of the long-running procedural.

"We're seeing some terrific talent. We're just in the process of trying to choose people that will help us continue to make 'NCIS' the best it can be," he said.

A greater description of the female FBI agent details how she can just as easily keep up with a group of politicians talking at a black-tie fundraiser as she can truck drivers at a roadside diner. In her mind, sleep and sex are "overrated" while a good martini and a rare bacon cheeseburger aren't.

Monroe is also a three-time divorcée (just like Gibbs), whose ex-husbands supposedly "can't keep up with her." Despite her toughness, she's also available as a shoulder to cry on and taking on the Mamma Bear role. But if you make her angry, she's not afraid to get mad at even her superiors.

Clarke is best known for her traitorous turn on "24" as Nina Myers as well as Bella's (Kristen Stewart) mother in the "Twilight" saga. She currently stars on the Amazon series, "Bosch."

The season's final two episodes will also serve as a farewell to Michael Weatherly, who has played Special Agent Tony DiNozzo's since the show's inception. Despite the casting of two new characters, Glasberg is adamant they are not meant to replace Weatherly.

"I can't replace Michael Weatherly," the showrunner said. "I'll just come right out and say that, and I've said it multiple times. He is not replaceable, but what we can do is find someone new, someone different, a new chapter for the show, and move forward and just find something quirky and new and different that works for all of us."

"NCIS" will return with a new episode on Tuesday, April 5 at 8 p.m. on CBS.