CIA's Nick Gehlfuss On Bill's Identity Crisis And How Far He'll Go For The Truth: 'Bill Is Questioning If He's A Psychopath'

The following contains spoilers for Monday's "CIA"!

Special Agent Bill Goodman has fallen even deeper down the rabbit hole of his father's past. And in the latest "CIA", his hunt for Felix Vincente took a wicked turn. 

In the episode's early moments, Vincente triggered a targeted explosion in the Upper East Side that killed an international arms dealer, causing Bill's personal and professional lives to suddenly collide. Still searching for answers, Bill dropped by Carl Shannon's for another visit. But after another inquiry into Vincente's whereabouts prompted Carl to pull a gun on Bill, Bill beat him to the punch, shooting his dad's former partner dead on the spot. 

After the team successfully tracked down Vincente (with a little help from Toni), Bill chased him into a factory and took him down, only he didn't hand him over to the FBI as he promised to Colin. Instead, he moved Vincente to a secret location that not even his partner knew about. "Now, you're gonna tell me what I want to know, or you're never getting out of this room alive," Bill threatened.

Below, Nick Gehlfuss talks to TVLine about Season 2's action-packed sixth episode including Bill's quest for truth, his unraveling mental state, and how the entire ordeal may be changing him as a person and agent.

TVLINE | Bill's dealing with shocker after shocker in terms of his family's past. What's been your favorite part of this whole arc?
NICK GEHLFUSS | Episode 6 is one of my favorite episodes of the show so far, but also of this 10-episode arc for Bill and his father. I'm so thankful for the storyline. Actors talk about "the moment before," we always think about that before a scene, but the moment before the season, Bill's coming back and his father has died. That's quite a circumstance to thrust him back into work, and coming back for the first day of work after bereavement leave. So already there was just all this juicy circumstance to play with. And then, of course, he has this bomb dropped on him that his father had this secret life. I'm filming Episode 10 right now, and it's so satisfying. I was praising the writers just a few days ago at how great they did with throwing everything up in the air and then bringing a beautiful culmination by Episode 10.

But Episode 6, I'm really proud of. It took a lot out of me physically and emotionally, but that's because it's that point in the story where we're at. Bill is going to be led down his darkest path yet because of Felix Vincente, the assassin, and if audiences were wondering if the clean-cut, buttoned up, by the book FBI agent was gonna turn, this is it. These are certainly the circumstances.

TVLINE | As an actor, what's been the biggest challenge for you in dealing with such heavy material?
The balance of emotional material and the physicality of the stunts. There's a lot of stunt work and an iconic subway sequence. It's just so New York. I like to do a lot of that. I like to do what I can as long as it's all safe. And we have wonderful stunt coordinators helping me through all of that. I don't do it alone, although I realize I'm kind of capable of it. I grew up playing sports and all that's coming back. It's fun. It's a lot of material. We do these in eight business days, and they're big episodes, big stories, and just all the technical stuff, all the balancing of it. It's great material and it's a wonderful gig. Living in New York and working in New York, there's nothing better, in my opinion.

TVLINE | Bill chases Vincente to a factory and there's a moment where he has a gun pointed on his target. Is he really thinking of killing the guy right then and there? Is he capable of that?
There's so much adrenaline, and the man tried to kill him multiple times. Let's not forget he tried to kill him at the cemetery in the first episode of our season, when we established who Vincente was. It would be enough for Bill, as a law enforcement man, to want to capture someone who got away from him, because he got away when he dove off the bridge. And then he finds out how wrapped up Vincente is into all this, and so it's adrenaline on top of this identity crisis Bill is in because he thinks Vincente potentially murdered his father. He thinks Vincente was potentially a better son to his father, or the son that his father never had. But he has the answers that Bill so desperately needs and wants. And so, if Colin didn't show up and stop him, it could have been a moment where he regretted what he could have done.

TVLINE | Bill does not give Vincente over to the FBI. Instead, he locks him away and no one knows about it, not even Colin. How far is Bill willing to go to get the information he wants?
I think Bill is willing to get rid of anyone or anything in his way to figure these answers out, and he's not going to stop until he does. It's going to take a toll on him. It's gonna be a matter of time before people find out. He is lying to expert liars. He has now divided himself from his partner. It's one thing for a partner to protect their partner from others. It's another thing to protect your partner from themselves, and of course that only works if the partner allows it. Bill is not allowing it. Colin's right. Bill has not taken the advice of Carl Shannon, his father's partner back in this Operation Palomar. He said, "You don't wanna go down this road. You won't like where it leads." And Vincente says something similar, and Colin also says, "You don't wanna go to the place it's gonna take to break a man like Vincente." Bill is not listening to anyone, clearly. Bill is severely being tested here. What will he do? That's what fans must tune in to see.

TVLINE | Speaking of this partnership, how has Bill's opinion of Colin changed since last season? Where do these guys stand in Season 2?
I think they're best friends, and they realize that whether they get all gushy about it or not. Bill committed to the CIA for a reason, [even] when he had a promotion at the end of Season 1. I don't think it was just the difference in work. It was this partnership. And so whether Bill knows he can lean on Colin to the fullest degree or not, Colin's there for him, and right now [Bill's] not letting him be. 

But I do think they are a fantastic team. They do protect themselves from others quite well. They've saved each other's lives. They've confided in one another, and they've been through a hell of a lot. They're soldiers together and they've been through the trenches, of sorts, and whether they talk about that out loud or not, it's all there. I think they have a wonderful partnership, but like I said, the partnership only works when both of them are allowing it to work, and Bill is certainly the one spiraling. He's got this identity crisis going on and he's in chaos, and he can't see reason. So a man that totally understands law, and cause and effect in all of this, he's not able to see that right now. He's blind to it. He's not doing what's best for himself even though he thinks he is.

TVLINE | With everything Bill's learning about his dad, how will this change his perspective of the CIA at large, and has it already?
Oh yeah, absolutely. I think Bill is questioning if he's a psychopath. And we've joked on the show that maybe that's what it takes to be in this profession. That's what Bill's afraid of. I think he's learning about the CIA through every case he works on since he's found out that his father was in it. He's understanding it on a deeper level. Even with Episode 2, he's realizing he should not keep the lie that his father kept from him and his family with his fiancé, so he does what he thinks is best. He's an honest man. He's a good man, but he's doubting it even once he told her. I think maybe he regrets telling her because he's in the doghouse. They're not doing well. He's sleeping on the couch. He's doing triple duty, CIA work, FBI work, and his own secret investigation. That is only sustainable for so long. I think Bill might be wondering if this was the right choice. I think he is questioning all of it and wondering if he should have ever taken this gig... or, worried that he was destined for this gig because of his father's potential darkness.

TVLINE | I do want to touch on the new Chief of Station. Olivia Markinson orders someone to look into Bill's background because she says she doesn't trust him. What can you say about what might develop in the next few episodes?
There's a time clock that's set once Olivia and her team start tracking him. It's only a matter of time before all of this closes in on Bill. When will Colin figure it out? How will Colin feel once he figures out? Will Nikki figure it out? At the end of Episode 5, Nikki says, "You have no idea what you guys are looking into and how far this goes, how deep it goes. If you're gonna look into Vincente, I wanna know everything." And Bill is not only not giving that to her, he's not giving it to Colin, and when Colin figures it out, will they right that wrong together or will they hold it for themselves? I can tell you that Bill is not going to stop until he gets the answers he needs, and I think by the end, Bill is going to look back on all of this and wonder if he should have done it. If he should have gone down this path.