A Knight of the Seven Kingdoms, the latest Game of Thrones prequel series from HBO, has been one of the most warmly received entries in the franchise since the original show ended back in 2019. A huge part of why A Knight of the Seven Kingdoms has connected so well with audiences comes down to the two actors at the center of it, Peter Claffey as Ser Duncan the Tall, and young Dexter Sol Ansell as his squire Egg.Their chemistry on screen feels completely natural and easy, the kind of thing that is genuinely very hard to manufacture. And now showrunner Ira Parker has opened up about exactly how it all came together, and the specific moment when he knew without any doubt that these were his two guys.The story Parker tells about finding his Dunk and Egg is actually a pretty remarkable one, especially when you consider how enormous the search was. The production put out a worldwide call and saw thousands of actors audition for both roles. What happened next, though, was something Parker clearly did not expect to go quite so smoothly.When the first batch of audition tapes for the role of Egg arrived, Dexter Sol Ansell was literally at the very top of the list, number one in the first package the casting director sent over. Parker watched it and immediately felt the role was filled.In an interview with TV Line, he said,"He was number one of the very first batch that my casting directors sent me, of like 15 eggs, and Dexter Sol Ansell was right at the top. Watched the audition, nailed it. OK, great, let’s sign him up. We, of course, went through the entire process and came all the way back to him, but he’s just a phenom."They went through the full process anyway, meeting dozens of other actors over several months, but every time, they came right back to Ansell. It just kept feeling like it had to be him.How did Peter Claffey become the only choice for Dunk in A Knight of the Seven Kingdoms?Finding Egg for A Knight of the Seven Kingdoms turned out to be the easier half of the equation. Finding Dunk was a different kind of challenge altogether. The character of Ser Duncan the Tall is described in George R.R. Martin's source material as being close to seven feet tall, which immediately ruled out most working actors in the industry.As Parker explained in the January 2026 issue of SFX Magazine, the physical requirement for the role of Dunk for A Knight of the Seven Kingdoms made it clear from the beginning that they were going to have to look outside the pool of established actors. Parker said,"Ser Duncan must be a very large human being. So, when you start there already, it cuts out every single actor in the world who has any experience. So, we knew we were going for an unknown."That search eventually led them to Peter Claffey, a former professional rugby player from Ireland who had only recently started acting. He had appeared in a Sharon Horgan series and had a small number of other credits, but he had never led a television show before. What won Parker and the team over, though, was not just his size or his look; it was the fact that every single time Claffey came in to audition, he was noticeably better than he had been the time before. The casting director kept telling Parker,"Every single time I see him, he is just exponentially better than last time."Parker brought Claffey back three, four, five times, and each visit made it clearer and clearer that they had their Dunk for A Knight of the Seven Kingdoms.The chemistry read that made everything fall into place for A Knight of the Seven KingdomsAs good as both actors were individually, it was the moment they stood in the same room together that really settled it for A Knight of the Seven Kingdoms. Parker has spoken about this moment across several interviews, and the emotion of it clearly still stays with him. In a recent conversation at HBO’s A Knight of the Seven Kingdoms FYC panel at the DGA, he said,"The moment you two stood in that room next to each other. I went, okay, we have a shot."Earlier, in an interview with TV Insider, he said,"When they were standing next to each other there, the way they related to each other just in an unspoken physical way was they felt like they had been brothers their whole lives, that they had grown up together."At a roundtable attended by Games Radar, Parker described sitting with director Owen Harris during the final chemistry read, and the two of them just looking at each other and knowing. He said,"We just looked at each other and we're like, this is the show. It was easy. It was the least stressful decision we've ever had to make and hopefully we'll ever have to make."That bond has only grown stronger since filming began. The two actors spent their weekends together building a real friendship, going to arcades, playing chess, and just spending time around each other the way their characters do on screen. A Knight of the Seven Kingdoms premiered on HBO on January 18, 2026, and has already been renewed for a second season, which is currently in production and expected to release in 2027.