'House of the Dragon' actor says 'GOT' prequel is just as shocking and surprising

Anticipation for the first "Game of Thrones" spinoff series has been hotter than a dragon's breath.

The opening episode of "House of the Dragon," premiering Sunday on HBO, has everything "Thrones" fans would expect from a sister show — love, betrayal, brutality, battles, sex, shock and, of course, dragons.

But amid the madness, a rare noble character, Ser Harrold Westerling, strives to uphold integrity in the fictional continent of Westeros.

"In a world of vipers, which is the world of anything to do with 'Game of Thrones' or 'House of the Dragon,' he's a straight arrow," said Graham McTavish, who plays Harrold. "He's a moral center in the story.

"He's not corrupt. He's not personally ambitious in the same way that other characters might be. He doesn't have that kind of agenda. So he represents something quite pure in a world where that's hard to come by."

The prequel set 200 years before "GOT," centers on House Targaryen and the members of that family that rule over the Seven Kingdoms of Westeros. They're the ancestors of Daenerys Targaryen, the silvery blond-haired beauty who was revered as a slave liberator before she unleashed her dragon to torch her enemies and innocents.

In "Dragon," Ser Harrold is a longtime Kingsguard who gets promoted by King Viserys Targaryen and is tasked with protecting Viserys and his first-born child, Princess Rhaenyra.

"Dragon" is based on George R.R. Martin's 2018 "Fire & Blood" novel. Martin also is a co-creator of the prequel show. McTavish avoided reading "Fire & Blood" before filming.

"I have a habit of really not reading the source material for these things, because in the end you're working from the script," he said. "I always try and approach these things without that baggage so it's a little more of a clean slate, so that you make your own imprint."

The 10-episode first season of "Dragon" will have a midseason time jump of 10 years. Some of the younger characters, including Rhaenyra, will be played by more than one actor.

"They do less-drastic stuff for me," said McTavish. "Basically, I had a darker beard in the first half. In my case, it was a slow deterioration from someone who was 50 to someone who was 60. I was very pleased. There were no wigs or anything like that."

But there was one thing he wasn't happy about.

McTavish said the shock factor of "GOT" was what helped draw him in.

"Right from that moment where poor old Sean Bean [Ned Stark] has his head chopped off in the first season, I was completely hooked," he said. "We'd never seen anything like that before. You're like, 'What? You're killing Sean Bean? This is going to be an interesting show.'