[Warning: this story contains spoilers for the fifth episode of Game of Thrones' seventh season, "Eastwatch."]

Before the credits rolled on last week's episode, Game of Thrones viewers were left with the haunting image of Jaime Lannister (Nikolaj Coster-Waldau) sinking to the bottom of a river, his fate unknown.

Well, only unknown within the context of the hour. Anyone paying attention to the series knew full well that there was still more business for the Kingslayer, as the very first scene in this week's episode made all too clear. "Eastwatch" opened up with Jaime gasping for breath as Bronn (Jerome Flynn) rescued his one-handed boss from death by drowning, just moments after he rescued the man from death by dragon fire. For a minute there, it looked like Jaime fully understood what his army's considerable defeat at the hands of Daenerys Stormborn (Emilia Clarke) meant for the Lannister cause. His secret rendezvous with his little brother Tyrion (Peter Dinklage) in the crypts of the Red Keep seemingly reinforced the losing narrative even further.

And then Jaime learned his sister was pregnant with his child, their fourth offspring together. In an instant, back to square one.

Before the season began, Nikolaj Coster-Waldau described Jaime's relationship with Cersei as an addiction, one he can't seem to break away from, no matter how many dragonfire-hot warning signs he encounters. The character's wavering in this very episode is a testament to the idea that Jaime is hopelessly entangled with his sister, emboldening the idea the Queen of Thorns (Diana Rigg) offered shortly before her death: Cersei will be Jaime's undoing some day — and vice versa, very likely. Read on for Coster-Waldau's thoughts on all of the recent events surrounding the general of the Lannister army, and a look ahead at Jaime's future.

Congratulations on Jaime becoming a father again!

Yes! (Laughs.) Thanks. It's a surprise to all of us.

Any gift suggestions?

An antidote would be great. Maybe some fire repellant. Maybe some really thick armor.

Really? You would think he might want to invest in some lighter armor.

Well, at least he wasn't wearing the brass armor when he went down. It was just the leather one. But Bronn is clearly a very strong and gifted swimmer. I guess that's why he said, "That's it. I've had enough. I'm out!"

Before we dig into this week's episode, just how much fun was it to film the Loot Train Battle?

Oh, I loved it. I loved every second of it. It was a long shoot. It took a long time, as you can imagine. I had a fantastic time. I love doing stuff like that. One of the great things about working on a show like Thrones is the way you do it, they believe in wanting to shoot in camera and have real stuff happen. Obviously, there's a CGI dragon that we can't have [practically], but most of the other things are there. You work with some incredibly gifted people. The set pieces, the train that's built, and you have the Dothraki … everyone from the stunt guys, who are all on fire, and you see the skills of the horsemen. It's just exhilarating. It takes a long time to shoot a sequence like that, but I really enjoyed it.

When reading that cliffhanger in episode four, were you nervous at all about Jaime?

When I read that he fell into the water, I went like, "Well, he's not going to drown." But when I read that he's going up against a dragon? I thought that was it. He's going to be fried. He's going to go out in flames. Let me put it this way: I was very quick on going to page one of episode five. I had those scripts lined up, and that happened quickly. (Laughs.) But I was very optimistic when he went into the water.

How would you have felt if he died there by dragonfire?

It would have been glorious. Well, not glorious, but a cool moment. If you're a Lannister, you would think that's a pretty brave moment. It's pretty ballsy to go up against the Dragon Queen. It would also have been a complete waste, of course, and very stupid, but that's beside the point! But those dragons are very terrifying. Fire is one of the biggest elements of this story, so it would have made sense. I'm very happy it didn't happen. When you're on the show for this long, you just want to keep surviving. I was talking to Lena, who plays Cersei, about how we always thought there's no way they would keep us around for this long. Every season, we expect this is going to be the one where we say goodbye. When we made it until season seven, and you knew there was only going to be one more? Suddenly it was like, "No, please! I really want to see what happens! I want to be around for the last year!"

"Do what you have to do next season, but please, keep me around until the premiere."

Exactly. "You can have me go out in episode one, that's OK. Just let me be there! I want to be there for the last read-through!" Because I think that's going to be pretty amazing. I want to get the tattoo, you know?

Episode five is a roller coaster for Jaime. He returns to King's Landing feeling crushed by the reality of Dany's forces. He reunites with Tyrion and comes to Cersei with a pitch to take the White Walker threat seriously. Then he learns he and Cersei have another child on the way, and it looks like he's right back where he started, firmly at her side.

Yes. And on top of that, there's that little tiny moment where he thinks, "Is this possible? Could I be allowed to be the father?" Because he's never really been allowed to be a father. He had that moment with Myrcella, the briefest of moments of feeling open about it, and now she's telling him that it won't be a secret. And so he's happy for maybe a millisecond before she goes ahead and ruins it by saying, "And don't ever betray me again." Suddenly, he's like, "Oh, that's right. It's Darth Vader. I forgot that I've been fucking Darth Vader."

Does it feel fair to describe this as a season of whiplash for Jaime?

Yeah, but he's doing his best! I'm obviously a little bit biased, but I think he's doing quite well! He's like, "Okay, I'm back in this dump again. Everybody wants to kill us. I have to make the best of this." He actually gets to do what he does best. He's a soldier. Now he's a military commander. As Tyrion says: "You were really smart! You outplayed and outmaneuvered me. That was very well done." Things are going very well. He's getting the troops back. He has the gold. They [won against] two of the Houses that were against them. It's all going very well. And then of course Daenerys comes in with her weapons of mass destruction, and it's all fucked. Of course, his sister is also still not quite willing to accept facts. She's just pretending: "If we're going to go out, I'm going to go out in a blaze of glory." I don't think he thinks that's the best solution. It's not easy. Certainly, he's trying his best.

Jaime and Tyrion reunite for the first time since Tyrion killed their father. What was it like shooting this scene with Peter Dinklage, your first scene together since season four?

Peter is such a great actor. It was such a great scene. And it's so much about what's not being said. They're not even saying what's really going on. I kept saying to the writers, "Why isn't Jaime saying the thing that must surely be on his mind?" Because Jaime tells him, "I told Bronn if I ever saw you again, I would kill you." And then Tyrion comes forward with this very impassioned and emotional plea: "Listen, my father wanted me dead." And yeah, that's true, I know that — why can't Jaime say the obvious thing? "Yes, I knew that, that's why I helped you escape — because you were going to get killed. But then you chose to walk back and kill him! You could have just walked away!" Because he didn't have to kill his father. He was gone. And of course, Tyrion isn't being honest. That's not why he killed Tywin. He killed Tywin because Tywin was sleeping with Tyrion's girlfriend. And that's another thing: nobody talks about it. It hasn't been mentioned since. Yeah, Tyrion killed Tywin, and yeah, Tywin was an asshole, but he also killed Shae, by the way. Why doesn't anyone talk about that? He killed this girl! She didn't have to die! That wasn't very nice! (Laughs.) It was just because he's jealous. My point is, there's so much subtext in this scene. Both of these guys have so much. You almost just want to shout at them, "Would you guys go sit down and talk somewhere? Find another setting. It's too fucking eerie here with all the dragon skulls."

Not the best environment for a rehabilitative conversation.

No, definitely not. I'm sure you can find a place in King's Landing to sit down and have some weed and talk it out. You need a good talk. I mean, they shouldn't smoke cannabis, of course. Have a drink.

Weed needs to get legalized in Westeros, first.

Exactly. Actually, surprisingly enough, that's one of the first things the High Sparrow (Jonathan Pryce) outlawed. No one saw that one coming. He really got people on his side when he did that. (Laughs.) Clever guy. That's beside the point.

Jaime battled a dragon and lived to tell the tale. Does that experience make it easier for him to accept Tyrion's story about the Army of the Dead?

Yes. And I think that's one of those things that's one of the themes of the episode. If you have a really close friend who tells you something, but it sounds crazy, but because you trust your friend, you're going to believe it. You may believe it, but you won't understand it until you experience it yourself. It's like someone telling you that they bungie jumped from a bridge in New Zealand and it was amazing. You're going to say, "Wow, sounds amazing!" You see the video and you go, "Whoa, that looks amazing!" But you don't really understand what it feels like until you've done it. I think it's the same with the dragons. You hear about the Dragon Queen and it sounds very bad that there's a lady with a dragon. Then you're standing there watching this Boeing 747 annihilate your whole army with fire. It's a thing to behold. I think it's the same with this. If Jaime trusts anyone, it's Tyrion. When Tyrion says this is real, he believes, at least, that they have to take this seriously. Why would Tyrion risk everything to come here and tell me this otherwise? So I think he believes him. But for all of these characters, even though Tyrion's plan is insane — they're going to capture one of these things and bring it to King's Landing to show Cersei — it might be clever, if they can pull it off. That's of course the big question.

You were Diana Rigg's scene partner for her final appearance on Game of Thrones. What was it like working together on Lady Olenna's swan song?

It was a great scene. It was beautifully written. She was and has been so brilliant on this show. It was fun to do a scene where she never loses her dignity and she never loses her intelligence. The fear never enters her mind. She stays strong and tough until the very end. It was a really cool scene. It was very fun to be a part of that, that's for sure.

Watch the video below for the Game of Thrones cast's preview of season seven's battles.

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