Photo: Getty Images

Nestled within the usual spy antics and will-they-won’t-they questions on this season’s Homeland was a smaller mystery: Who is this Peter Quinn character, and why does he get so mad all the time? The answer, as revealed on last week’s episode (obligatory spoiler alert), is that he’s a black ops agent of some kind — and he was put on the team to kill Brody when the time comes. Vulture caught up with Rupert Friend, who plays the terse, violent Quinn, to discuss his big secret, anger-management issues, and what Mandy Patinkin sings to him on set.

So, you’re a super-shady black-ops agent! That was quite a reveal. Have you known the whole time?

Yes, but in a very super-secret, shady way. [Laughs.] When I first arrived — I think because I was the new guy, and possibly to sort of calm my probably quite obvious nerves — the directing EP and one of the writers took me aside and in a very vague way sketched out some of what was going to happen. I later found out that they don’t actually tell you everything because they don’t know.

How much did they tell you?

We were on the lunch wagon, so I think they were trying to keep it pretty hush-hush. It was all kind of mimes and raised eyebrows and kind of mouthing what was going to happen.

How do you prepare to play a dark-ops CIA agent? Or can you even, besides playing video games?

Playing video games! That’s a good one! I think I will actually explore that one next time. Find the appropriate video game and play it.

It’s Call of Duty, I think.

Oh, brilliant! So that means there’s already one. Well, then, I’ll just play that until I know how to beat the person.

Quinn tends to get a little riled up — I’m thinking of the knife scene in particular, when he stabs Brody in the hand.

One of the things I do know first-hand from somebody who works in this arena is that an anti-patriot or a terrorist is hated, like personally hated by someone in the kind of role that Peter Quinn finds himself in. They hate people who try to damage or destruct the safety of their country, everything that the Constitution stands for. They’re really very fierce about it. So there is an extreme there, which, I think, is possibly exacerbated by Brody. Brody has a very smug way of getting out of it, kind of saying, “Well, hey, at least it didn’t go off,” and it’s like, that’s not really the point. And that’s sort of annoying, and is therefore enraging.

And also, it turns out Quinn was playing bad cop.

I think that’s up for debate.

Do you?

I don’t think there’s a definite answer on that. We talked about it and here’s an argument for both sides. There’s an argument saying that it was a very clever piece of setup so that Carrie could come in and finish the job in her way. And there’s another saying that the guy has got anger-management issues. [Laughs.]

Are you aware that there is a small contingent of viewers that are rooting for a Carrie-Quinn romance?

No, I didn’t know that. I didn’t know that. But um, I’m glad somewhere in the world someone is rooting for Quinn in some way or another.

As a viewer of the show, what do you think of the Carrie-Brody relationship?

Well, I stopped watching it for this season. So I’m not sure. If I was basing it off the first season, because I can’t base it off more than that, I would … yeah, it’s very complicated. She’s pretty volatile.

You’re British, as are Damian Lewis (Brody) and David Harewood (Estes). Everyone in America would like to imagine that you three formed a little British club and sit around all day comparing accent notes. Is this true?

Uh, no, no, no. [Laughs.]

You have a lot of scenes with Mandy Patinkin. Did he ever sing to you?

Yes, he does. He sings little show tunes, which are fine, you know. I went to see him singing live, and he’s phenomenal. He did “Bohemian Rhapsody” and blew my balls off. It was amazing. So he does that, but he also does whole made-up songs if he gets bored or things are moving slowly. He sings in a very operatic style, like, “Why are we waiting?” which comes across really well, because he has a beautiful voice and for that twenty seconds, no one realizes what he’s saying until you realize he’s making a joke about your bum or something.

Was it about your butt specifically?

Well, we both had a thing where one or other of our bums used to be in the front of the shot. There was a point where we thought at one point, maybe they were trying to put us against each other and sort of make us compete about bottoms. And Mandy did something really quite inappropriate, which I’m not going to divulge. But put it this way, you wouldn’t expect it in a room full of consenting adults. While singing. Which is something I didn’t think I’d be faced with in my entire career.

You know, not many people have that story.

Nope, and I kind of felt privileged and repulsed in equal measure.