Jaime Lannister vs. Brienne of Tarth: Who's the Better 'Game of Thrones' Fighter?

Gwendoline Christie and Nicolaj Coster-Waldau in the "Game of Thrones" Season 2 episode, "Valar Morghulis." (HBO)

After Nikolaj Coster-Waldau and Gwendoline Christie walk into a room, it takes but a minute to realize the actors are perfectly matched sparring partners in real life as they are as characters Jaime Lannister and Brienne of Tarth on "Game of Thrones." The only difference is their weapon of choice is sarcasm, not swords.

Paired at last week's Beverly Hills, Calif., junket for Season 3 of the series inspired by George R.R. Martin's "A Song of Ice and Fire" novels, the war of wit and words began immediately when a reporter asked if the empty chair between them at the roundtable symbolized the rift between their "GoT" alter egos.

"Yes, yes it does," Christie (Yes, she really is that tall!) deadpans.

"I was going to sit there, but she was very quick to put her bag down," Coster-Waldau counters.

"It's his handbag. He makes me carry it," Christie adds, putting on a meek voice.

Coster-Waldau dropped his head, shaking his unruly blond locks. "Gwen, you have to realize when it comes into print, they won't hear that you aren't being serious. We were at a junket in London, and afterwards people said, 'You're really angry with each other.' And we go, 'What do you mean? We're just having fun.' It is just pure joy to be rude to Gwen, and it was so much fun to work with Gwen."

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As are the fans who get to reap the rewards of the spectacular chemistry and undeniable bond these two share as the third season picks up immediately where it left off with the pair last year. The King Slayer is being unwillingly escorted by Brienne back to King's Landing at the behest of Catelyn Stark, who hopes he can be traded for her daughter Sansa, who is being held hostage. They reminisced about last season's canoe portion of the journey. "I learnt to canoe in the dark and rain the night before we shot the scene," Christie recalls.

Christie wasn't about to let her adversary get the last laugh. "Whereas I just found it bland. You're fine, but I didn't have a particularly good time. I enjoy the work, but I sometimes wish you'd be there when the camera is on me and not back in your trailer." She held her face straight for a few more seconds before busting out in a hearty guttural guffaw. Finally getting serious, she said, "I really love working with Nikolaj. He's taught me loads as an actor and really takes care of me. I'm really very, very lucky."

"To her credit, her costume is very cumbersome. It's like the Tin Man walking around. I was generally worried for you. I thought if you go under in that outfit, you'd probably not come up," Coster-Waldau adds. "I also couldn't stop laughing, because it looked very funny."

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The actor could channel those feelings into Lannister's plan to drive Brienne crazy. He succeeds in annoying her so much that she drops her guard just long enough for him to get the upper hand. The ensuing battle on a bridge will have everyone wondering who is the better fighter.

Catch a glimpse of their sword fight on the bridge at the 19 second mark: 

"As actors? He is absolutely. You pick it up in seconds," explains Christie. "But Brienne of Tarth is clearly better than Jaime Lannister. It's why I work so hard. I have a lot more strength. I don't rely on tricks or flowery elements to distract. Everything is very simple straightforward shapes."

"She's just brute force. No style. She scared me for real," Coster-Waldau agrees. "We'd been fighting all day, and it was a take at the end of the day. She was hacking down on me, and there was one point where she hit me so hard that the sword hit me in the head."

She returned to sarcastic ribbing. "This tiny little kitten was mewing, 'Can you just take 10 percent off of the force please?'" [But] it really released a lot of tension that you had built up through antagonizing me onscreen and off. You kept hitting me on the ass with your sword, and I thought it was inappropriate. That moment was so rewarding."

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They both insisted they suffered no injuries, but they couldn't promise their characters would find such happy endings. Christie wouldn't comment on whether they make it safely over the hills and through the woods or on early reports that Brienne brawls with a bear. "I ruined it for myself before I even got the part [doing] research, but you never know what's going to happen. What David and Dan do so brilliantly is maintain the integrity of the books while capturing the story in many different ways. I think of it as having a psychological guideline and the foundation of the character, but it can go in any direction."

Coster-Waldau has also read the books to discover his trajectory and admits that he, like everyone else, always asks the novelist. "'When do we die?' It's going to be interesting this season; that count might come up," he foreshadows. "There are scenes this season that I knew from Day One would come up, and I was very curious to see how they'd come out in the script. Some of it is very tricky to adapt, because most of the big changes in the character are internal."

The answer left the gathered journalists that day wondering if the show's increasing popularity puts more pressure on the cast to up their game. "You can't allow yourself to start worrying about what people will think, but we are very aware of how special this is," Coster-Waldau said. "Obviously, we want to live up to expectations, but our own expectations are as high as the fans' are. We've had that passion for it from the word 'go.'"

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The inner drive to excel didn't prepare them for the enthusiastic and often strange fan interactions they would encounter, though. Christie says, "Most of the time people are just really nice, but [one time on Twitter] a man said he would like me to grind his pelvis into dust as the character. My eyes opened wide. There was [another] time in Belfast where a white van full of men who looked like they'd been manual working shouted across the road, 'Kill us. Kill us.'"

She looked at her co-star to be regaled with his tales of wild fan interactions, and it was his turn to slip back into sarcasm. "Oh, I always carry a sword now so people stay away from me."

"Game of Thrones" Season 3 premieres Sunday, 3/31 at 9 PM on HBO.