The actor also reveals how he mastered Bran's intensely creepy stare and what he knew about what Bran saw in that tower back in the pilot.
Jimmy Kimmel was feeling pretty confident that he could lure a "Game of Thrones" spoiler out of Isaac Hempstead Wright on "Jimmy Kimmel Live," Wednesday night, and he may have gotten a kernel of something.
"Help me, HBO," the actor who portrays Bran Stark said after Kimmel had him cornered regarding that internet theory that Bran somehow becomes the villainous Night King.
Jimmy slid smoothly into the spoiler-y question sideways with an innocent question about the crippled young boy who has become one of Westeros' creepiest denizens.
"Do you think Bran is 100 percent good?" Jimmy asked Isaac.
"I don't know," Isaac said cryptically. "I think he's the three-eyed raven who is definitely on the side of the living."
Jimmy immediately latched onto this statement as a possible confirmation that there is no way, then, that Bran could be the Night King who commands an army of the dead. "I can neither confirm nor deny," Isaac said of the theory.
"I feel like you confirmed," Jimmy insisted. "I mean, if he's on the side of the living, unless the Night King is some kind of weird double agent."
"Who says the Night King's dead," Isaac said, and the immediately called out to HBO for help. Is the young actor just trolling Jimmy and the fans at this point, or did he let slip something? If so, it wouldn't be the first time, as he confessed he accidentally dropped a major spoiler in a math class about the fate of a key character on the show.
He and Jimmy also talked about that intense staredown between Bran and Jaime Lannister in this past weekend's Season 8 premiere. And when asked about it, Isaac had a pretty good explanation for why he's able to give such an unsettling stare, beyond even being a part of his character.
"I'm kind of getting good at this sort of intense stare, but it's actually aided by the fact that I'm completely blind when I'm on set," he said. "I don't have my glasses and I don't have contact lenses."
He recalled a scene from Season 7 he shared with Sophie Turner, who portrays his on-screen sister Sansa. "She said, 'Isaac, your stare is like you're staring into my soul," he said. "I was like, 'I can't see you. That's why.'"
He also didn't see, per se, that infamous scene that got his character pushed off of a tower way back in the pilot, and that precipitated the weight behind his reunion with Jaime Lannister -- the man who did the pushing, and who his character hasn't seen since that moment.
In the scene, Bran was climbing the tower when he came up on Jaime and his sister, Queen Cersei, engaged in the carnal act. And while then ten-year-old Isaac didn't actually see the scene as played out on-screen, that didn't mean he was completely in the dark about it.
"I was pretty much told what was going on," he said. "It just sort of meant that my mum had to give me the sex talk a little earlier and with some sort of topics that probably aren't covered by general sex talks."
For example, if you find yourself attracted to your sibling, "Don't act on it!"
"Game of Thrones" continues its final season Sunday at 9 p.m. ET on HBO.