CIA's Tom Ellis Says FBI Spinoff's Two Leads Are 'A Bit Like A Bickering Married Couple'

When Tom Ellis was first pitched the idea for "CIA," the forthcoming spinoff of the "FBI" universe, his ears instantly perked up. Not only did it give him the chance to work with Dick Wolf's acclaimed production company Wolf Entertainment, but the two leads' "Odd Couple" dynamic along with the series' strong character work immediately piqued his interest. 

"Dick Wolf's got such an incredible track record of making successful TV shows," Ellis tells TVLine. But the series' major strengths, he notes, go far above and beyond its cases of the week and overarching plot. 

"We don't just live at work with these characters, we follow them home, we find out about their private lives, and we find out about what makes them tick," he says. "Coupled with the fact that any time that I've spoken to people that work in law enforcement or in the darker sides of life essentially, their way of coping with it is to have this kind of gallows humor. There's a humorous approach to it because it takes away from the darkness of the work they're actually doing. I was quite interested in bringing that kind of dynamic and some levity into the show, which you wouldn't always associate with some of the Dick Wolf stuff."  

While "CIA" isn't written like a comedy, Ellis does hope the audience is periodically laughing because as he puts it, the show's two leads are "a bit like a bickering married couple at times." 

In "CIA," Ellis plays Colin Glass, a man who's described as a secretive and roguish CIA case officer. When the series kicks off (tune in Monday, February 23, at 10/9c on CBS), he's partnered with a do-gooder, by-the-book FBI agent named Bill Goodman, and together, "They will work covert operations in New York, uncovering international plots, terrorist cells, and geopolitical secrets," according to the official description. "On CIA, Bill will learn the rules of this murky world on the fly as Colin leads him deeper into spy games where only one thing is clear — their work keeps America safe, even if no one will ever know what they did in the shadows."

The yin to Colin's yang is played by Nick Ghelfuss, who's perhaps best known as Dr. Will Halstead on NBC's medical drama "Chicago Med," also helmed by Wolf. With Colin's habit of coloring far outside the lines, Bill is there to not only liaise between the two agencies, but also to keep his new partner in line — a feat that may be far more difficult than Bill could've ever imagined. 

"Nick's like a dream," says Ellis of his new co-star. "He's worked on a long-running show before. He knows what to expect when you come to work. We approach work very similarly. We're both big on script, we're both big on detail, and we both ask a lot of questions. We're always trying to improve and embellish what's already there on the page. And he's just got a great attitude, but [is] also incredibly kind and conscientious and just great with everybody. It's quite a punishing schedule, but we laugh together which is always the best way." 

While the real-life relationships on set are copacetic, it's bound to be a bumpy ride for their characters, Colin and Bill. Each man has a very different approach to how he conducts his work and just how far he'll go to protect the American public. 

"Colin predominantly deals in lies, even to the point where the lines are blurred between the truth of his own life and what he presents to the world," says Ellis. "As a CIA operative, you can't let hardly anybody into your inner circle and you're always cultivating what your image is to other people. So Colin's job is to essentially lie all the time and that's one of the things that Bill finds difficult being his partner, because he doesn't know when he's getting the true version of him. He doesn't know whether he can trust what he's saying. [Colin] basically lives on the edge of the truth constantly."

As previously reported: There will be crossovers, aplenty! 

"FBI" star Jeremy Sisto will guest-star in the series premiere as Assistant Special Agent in Charge Jubal Valentine. It's he who ultimately pairs up this special CIA/FBI duo, launching Colin and Bill's unique partnership into the great unknown.

"When Colin is asking for a partner in this, he's asking for someone that he can walk all over, who just lets him do everything and get away with everything," says Ellis. "And Nikki, Colin's boss [played by Necar Zadegan], decides that when she goes to Jubal, she's going to ask him for exactly the opposite because Colin actually needs more help than he lets on — not just help for the case, but help for himself as a person. I think she feels like he's drifting a bit in his morality." 

Sisto isn't the only "FBI" star who will rear his head in the spinoff. Alana De La Garza (Special Agent in Charge Isobel Castille) and Missy Peregrym (FBI Special Agent Maggie Bell) will also appear later this season. But the details of their big crossover episode are being kept under wraps for now. 

Will Bill and Colin's colleagues at the FBI and CIA be the glue that binds them together? Will these very different forces of nature be able to play nice? And is Bill ready to play in the CIA's morally gray shadows alongside his new partner? 

"I think from Colin's point of view, Bill isn't ready," teases Ellis. "He's too a*al-retentive, he's too dead-set on, 'This is how I do things and this is my methodology.' Colin believes that in order to be working with CIA, you need to be malleable, you need to be able to adapt, you need to be able to not get caught up in the morality of a situation. You just need to be focused on getting the end result."

Will you be watching "CIA" when it hits CBS Monday? Sound off in the comments below!