There are but three episodes remaining in the second season of "The Americans," and in this week's new installment, "Stealth," the character who's been a great surprise all season — Costa Ronin's Oleg Igorevich, the Soviet Embassy's new science and technology officer — gets a major surprise himself.

No worries, that's as big a hint as we're giving. But Ronin talked to Yahoo TV about his character's impact on the series' sophomore season, and he's hinting that there are plenty more surprises ahead from Oleg, perhaps stemming from his true motivations at the Rezidentura or his relationship with fellow Russian spy Nina. Either way, he's got us convinced that Season 2 is going to end as grippingly as it began and that both Oleg and Nina will play big roles in the story.

When we first meet Oleg, he's very cocky, but he seems like someone who only has his job because of his father's position in the government. We quickly learn he's much savvier, and more ambitious, than he first appeared. How much did you know about the character when you were hired?
The only thing I knew was what I had read in the first two episodes. I did a lot of work preparing for the part, so when I got on set, every idiosyncrasy that you see on screen is not me as an actor, it's the character. I needed to create a whole character. I needed to find out not just what he eats and drinks and how he thinks, but how he feels. I needed to find out about his heart. It's one of those environments, it's one of those shows, where characters do not show what they think, which was another interesting aspect of creating that character.

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Going in with Oleg, I knew that his father is a very high-posted official back in the Soviet Union. I knew that he grew up in the ranks of nomenklatura, which is like, not a middle class or upper class... it's kind of a class of its own that doesn't really answer to any of the rules. They almost run the country. But I also wanted [Oleg] to be a human being. This is what this show is so good at. It's not just about the good guy and the bad guy. It's about the people. It's about how what we do makes us feel. It's about what happens when we get home after doing our job, and we have to help our kids with homework, and we have to pick up groceries, and we have to meet for drinks and hang out and be ourselves. Can we really let go of our profession, even then? Can we really stop being a spy?

Oleg Igorevich character profile:

How did Oleg become this major player, so quickly, at the Rezidentura?
[Showrunners] Joel [Fields] and Joe [Weisberg] have put together such a terrific team of writers, who really are able to give the audience glimpses of that. When you come into an environment like [the Rezidentura], you can't come in soft. You cannot come in strong about the spy game. You have to come in very much under the radar, where nobody is expecting any moves from you. Nobody is expecting anything from you. Everybody kind of lets you be, so you can just, in the shadows, watch everybody, learn about everybody, gather intelligence about everybody, figure out the playing field. When you watch people when they're relaxed, that's when you learn the most about them. That's when you really learn about who they really are. Not when they're talking to each other.

So Oleg learned more about Arkady when, not when he was talking to Arkady, when he was just watching Arkady do his thing day after day after day. He was learning everything about Nina when he was just watching Nina interact with other people or just sitting there at her desk or when she was running out to meet with Beeman. These are all the facts that were helping Oleg understand what really makes Arkady tick, what really makes Nina tick, what really makes everybody else tick. Then he figured out the playing field, what the power plays are. And then, once he knew that, only then he was able to... I think the turning point was that scene where Arkady and Oleg were discussing the extraction of the scientist. This is the first time Oleg comes out and says to Arkady, "Look, I am actually quite good at this." And the two bond over this whole experience, and it goes from the old wolf and the young wolf kind of setup to an almost fatherly setup, an older brother setup between them. At the same time, we still have to remember that it doesn't matter what the audience sees... nothing is what it seems. It's all about nothing is what it seems.

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How did your role on the show come about?
Last August, the casting brief came out, and I put together an audition tape. Then Daniel Sackheim, an executive producer and director of the show met with me, and then I had to go through that round of auditions and do a few scenes. Then Annet [Mahendru], who, of course, plays Nina, was here in L.A. as well, and we met, and we had a chemistry read, and that was it.

I just let go of it, and I was at a table read for another project when I get a call from my agent saying that I got the part, which was great news. I knew that there was going to be a part for two episodes. I didn't know that was going to turn into the whole season. As we know now, it kind of ended up being a completely different journey, which is a phenomenal credit to the writing team, that they were able to almost create that new character in the show, and the storylines, and the throughlines. It's a terrific experience, you know? Now seeing the show on TV and seeing how well it's received, I'm very proud to be, very humbled as well, to be a part of this journey.

Watch a clip from the next episode of "The Americans":

Oleg's relationship with Nina was a surprise — a really nice surprise — in this season. Was there a special chemistry between the two of you when you first read together?
You know, something happens when... yeah, it wasn't just two actors working together in one room. We connected not just on the human level as people and as fellow actors, but we also connected on the cellular level. I hope that's something that comes to life onscreen, something the audience can see. Something happens when two people look at each other, and they have a cellular connection. It's like when their hearts connect, as well as their souls. The journey for me and the journey for all of us this season is so huge, and we didn't know [initially] that the characters were going to be romantically involved. We didn't know where the writers were going to take the story. But as actors to be able to tap in to that and have that chemistry and have that cellular bond, it's phenomenal. It's like real life, you know? When you meet somebody and you have that connection, everything is just so much easier.

[Photos: Check Out More Pics From 'The Americans' Season 2]

What's your favorite Oleg moment so far this season? Is it one with Nina?
I think one of the big turning points for him was the polygraph test with Nina because he knows a lot about her. He knows a lot about her as a person and also about her as an officer. The first scene, when he and Nina and Arkady are talking, and she really freaks out about the polygraph test, he knows this is her weakness. He knows she's got weaknesses and that he's tapping into her social weaknesses. When he teaches her how to pass the polygraph test, when he gives her all the ins and outs, the tricks [and she passed the test]... the beauty about that is that not only is he happy that he succeeded as a teacher, but also that she succeeded.

He also understands that he has just created a monster. He has just created another superspy, who cannot be stopped by anything now. She had everything else going for her. She's an incredibly beautiful, smart woman, who knows exactly how to play her cards and knows exactly how to do her job and move up, but now he's given her something that she didn't have. He knows that he's giving her the secret weapon, and he still gives it to her.

Is that because he genuinely cares about her?
Absolutely. He does genuinely care about her. The thing about this, not just the show, I guess, but about that world, is that they're still people. They're still people with needs and wants and desires. They just go differently about those things. They're just not as open about their wants and desires. They just manifest them differently. But they still have them. They're still human beings. They still want to party. They still want to drink, still want to have families and have babies and fall in love and have a future.

Oleg comes in, and it's almost like he's playing a completely different spy game, on a different level. You know, it's not about just being there for your country. It's also about being there for humankind. It's not just about which country wins. It's about the balance, and it's about us as countries and us, the officers, at the front line, being in a position to change that, being in the position to not just push that wall forward or tip the scale to one side, but make a difference in the world, make a difference in the way humankind lives and operates.

If you and I were having this conversation after the season finale aired, I'd be able to discuss a little bit more.

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As your role on the show, and Oleg's role within the Rezidentura has expanded, he's figured out what makes everyone else tick, as you said. But there's still a lot of mystery about him. Do you know what makes Oleg tick at this point?
Oh, I know. [Laughs.]

But we, the audience, don't yet. Have we seen the thing that really makes him tick, what's motivating him?
No. You've seen glimpses of his decision-making process, but you haven't seen it all yet. No, no. You will see more of it in the next, what is it, three episodes we've got to go? In the next three episodes of the season, you will see more of it. You will see more of his heart. You will see more of his... I don't want to give up too much, because I want it to be exactly as it's intended. I want the audience to go on the journey and discover it for themselves, so I'd hate to rob the audience of the opportunity. I would really love to see what the reaction's going to be to what's coming up.

So there are definitely some surprises coming with Oleg?
Absolutely.

You grew up in Russia. And since there were just a couple of episodes written for Oleg when you got the role, did you have a hand in shaping him and his experiences, based on your own background?
You know, I was very young when the elections took place, but I was around when the Soviet Union disintegrated and when the Berlin Wall came down, and I remember how it affected the society. I remember how everything was great one day, and then the next day almost everything went… everything changed. All of a sudden, people didn't know… you have a passport that says you were born in the Soviet Union; you're born in a country that no longer exists. It's a very bizarre experience, you know? So talking to people who were adults in those days, who had interaction with the KGB, who were living those lives that we are living right now onscreen, I was fortunate enough to talk to some of those people and get their stories and also see how it made them think.

Back when I was still in Russia, I was sitting down with this one gentleman, an older gentleman, and he was telling me these stories about his life, and during the conversation, he had a tear in his eye. When I sat down with him, he was just tough, like, imagine Arkady 20 years down the road. It's like tough as nails, old school, nothing bothers him, nothing can shoot that man down. I was talking to this gentleman, and at the end of the conversation, he had a tear in his eye. It's when [people] open up, only when they open up and you can see glimpses of their heart and their soul, that's when you know you're getting somewhere. I'll tell you what, that one man, he was a terrific human being, and I've learned so much from him. And a lot of what I've got going in Oleg, a lot of what I've got going with his thinking process, I learned from that man.

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So, to answer your question, yes. Living in Russia, being in Russia, it helped me step into this almost collective cultural heritage, collective cultural knowledge, and then, again, as an actor, everything else had to come from everything I can get my hands on.

I don't see myself as an actor. I see myself as a storyteller. If there's an opportunity to tell a story through acting or directing or cinematography or a book, I will embrace that opportunity. I just felt that urge, that need to know before that generation goes, before the world changes, before we all are the same. You know, speaking the same language, living in a futuristic world, and eating the same food. As long as the human aspect of our society, of us as a race, is alive, it's our duty to tell those stories.

We are near the end of Season 2, and it's gone by so quickly. Do you know what might be ahead for Oleg in Season 3?
I have no idea. It's all in the hands of [Joel and Joe] and the writing team. The interesting thing about doing television versus a film or play, when you do a film or play, you know how the story starts, you know how the story ends. You know about the lead character and where the character starts and goes, too. But when you do television, you have no idea. You are working on one episode, and then you get a script for the next one, and that's how you find out. "Next week, you're going to, you know, you're not going to die, don't worry," or "You're going to fall in love and kill a couple of people, so you'll be fine." I'm looking forward to it either way; either being on the show or watching the show, because it's a terrific, terrific series, so intelligent, and I'm so, so glad that story is being told.

You also have a role coming up this summer in the CBS drama "Extant," with Halle Berry. What can you say about the show or your character?
I play a scientist. It's a much smaller role than Oleg, but they're still filming, so hey, who knows, right? First of all, it's a different show altogether. It's a futuristic show as opposed to retro like "The Americans." I play a scientist in the future who is… actually, I don't think I can really tell you much about it. But I play a scientist, and it was a terrific experience. I'm really excited for the fans of Halle Berry, because she doesn't do television often, and I think it's going to be quite a ride.

Watch the "Extant" trailer:

"The Americans" airs Wednesdays at 10 p.m. on FX; "Extant" premieres July 9 at 9 p.m. on CBS.