Spoilers ahead for the most recent episode of Game of Thrones.

Jaime Lannister was always Tywin Lannister’s favored son, but he never seemed to be the man Tywin wanted him to be — until now. Some of this wasn’t by choice — leaving his job as Lord Commander of the Kingsguard, or being a “glorified bodyguard,” as Tywin saw it. But leading an army and completing the siege of Riverrun is a move his father would have applauded, especially in the cold-but-pragmatic manner in which Jaime executes it. (Using the groom from the Red Wedding is just the icing on the, um, Red Wedding cake). “Jaime’s becoming his own man now,” Nikolaj Coster-Waldau says. “Whether he wants to or not, he’s taking care of the Lannister legacy. He has to. There’s no one else left.” Coster-Waldau chatted with Vulture about Jaime’s ruthless move, reuniting with Brienne, and twincest haircuts.

Brienne finally reunites with Jaime! But not under the best of circumstances.

Yeah, what I like about it is the scene just before Brienne and Jaime, between Bronn and Podrick, when Bronn says, “Do you think they’re fucking? I know he wants to fuck her. And I’m sure she wants to fuck him, too. So what do you think?” Because it’s that thing when two people are attracted to each other but they refuse to acknowledge that whole elephant in the room, and for everyone else around them it’s pretty obvious. And then, of course, when we cut to Brienne and Jaime, it’s very formal. It’s very correct. [Director] Mark Mylod, the way he staged it was very clever. He kept having us separated by furniture. There’s always a table between us, until the very end of the scene, and when they finally get close, it’s this heartbreaking moment. Usually when you get this close to someone you care about, you say something like, “Please be safe. I can’t wait to see you again.” And here it’s like, “If I see you again, we’re probably going to have to try to kill each other.” I love doing those scenes with Gwendoline, because there’s so much subtext. They never really say how they feel. They kind of decided long ago never to go into that area. And they’re both in a very difficult position. She says, “I need the Blackfish, I’m on this mission,” and he’s like, “You can’t ask me to go against my family.” They’re both bound by these promises they live by, trying to do the right thing, the honorable thing. This code, if you will.

It’s complicated, of course, by the fact that Brienne is with Team Sansa because of Jaime.

Yeah! He saved her life, and then he gave her the armor, the sword, and that helped her survive the battle with the Hound. He wants nothing but good things for her. But he’s obviously constrained by who he is, and where he is.

There’s a strange parallel in how Edmure Tully is now Jaime’s prisoner, considering how Jaime had once been the prisoner of Edmure’s family, of Robb and Catelyn Stark. Perhaps he’s reminded of that when he first sees him, and it’s why he insists that Edmure be bathed and fed.

Absolutely. My favorite scene, the one I most enjoyed shooting, was the one with Edmure, because it’s such a beautiful piece of writing. What I love about it is that there is so much violence, so much buildup, and we expect this big battle, and Jaime outmaneuvers Edmure by basically saying, “When all is said and done, all of us, if we have children, we’ll do anything for our children. You have a son, you love him dearly, and so this is the situation. You either do as I want you to, or I will bring your son here, and I will launch him into Riverrun with a catapult. I’ll kill every person you hold dear, if you don’t do as I say.” And you’re pretty convinced that when Jaime says this, he will do that. It’s like what he said to the Frey brothers — don’t make threats unless you’re prepared to carry them out. A little leverage is a good thing to have.

Clive Russell, who plays the Blackfish, described Jaime’s manipulation of Edmure as slimy. Where on the scale between ruthless and slimy would you say it is?

Extremely ruthless. But also very honest and strategic. I don’t see it as slimy at all, but maybe I’m biased! He makes it very clear there’s a choice. There’s always a choice. You can choose violence, but it always breeds more violence. Edmure, of course, gets very upset and tries to argue and calls him names. But Jaime doesn’t care about any of that. It’s very tough to watch, and you might feel, “What a bastard!” It’s terrible, but this is saving thousands of lives. Jaime could attack, but it would take a long, long time. It would take forever. It would be good for HBO, because the show would last another few seasons! [Laughs.] But now none of the soldiers die. Everyone survives, except the Blackfish, and that’s his own choice, because he wanted to die in his castle. But Jaime avoids a massive battle, a massive loss of life, by just pointing out the obvious: “Yes, we could have this battle, and you could be honorable, do the right thing, and never surrender. Or you can surrender, and everyone will walk away alive and go back to their families. And you can be reunited with your family.” In a way, it’s like what Tywin did, with the Red Wedding, which was a horrible, horrible thing, but it stopped the war. Thousands and thousands of soldiers were saved. So what’s more important — these 12 noble people of extreme privilege, or thousands of men and women who didn’t ask to be a part of this war, but had to be, because of whatever families are in charge?

We’ve talked before about how you’re obsessed with Bran, and you think he’s going to be important for the endgame. Now we’re seeing the scope of Bran’s visions and powers, including how Jaime killed the Mad King …

It was great. The actor playing the Mad King was brilliant. And it was kind of weird, because at one point they talked about casting a younger version of me, but then they realized that they only needed a few bits, so it was better to have my body, my movement. But it was a surprise, when I read the script, because [showrunners] Dan [Weiss] and David [Benioff] were always so adamant that they were never going to do flashbacks. They just lied! [Laughs.] And when you read those sequences, it’s one of those wonderful things when you realize, “Wow, I can’t see where this is going, but it’s so cool, and so interesting!” Bran and the whole Hodor story line, what a buildup! It took six years for that to pay off, and it was really worth it.

And now I’m even more excited about what Bran is about to become, just to see how that will play out. And I’m wondering, “What if Jaime hadn’t pushed Bran out the window?!” Because Hodor was already like that, in episode one! So what came first? Was it already meant to happen? That whole timeline, you have to wonder how much the Three-Eyed Raven was involved with Bran being at that tower, at that exact moment when Jaime and Cersei were there? Now I’m just another guy speculating. [Laughs.]

And Jaime and Cersei now have matching haircuts, which is a little creepy …

I know. [Chuckles.] Finally we look like twins! It’s scary. And Joffrey had the same haircut, and Tommen had the same haircut. Apparently, there is only one hairdresser in King’s Landing! We all run in and say, “Just give me whatever.”