Matt Smith is certainly no stranger to high-profile projects. For years, the Emmy-nominated actor popularly portrayed the late Prince Philip, the Duke of Edinburg, in the Netflix hit series The Crown. At the same time, the actor has done some big-budget movies including Morbius and Terminator Genisys.And so, when it came to the Game of Thrones (GoT) prequel House of the Dragon, fans may have expected Smith to take to his new role as Prince Daemon Targaryen with some ease (although some have argued that he doesn’t look Targaryen enough). As it turns out, however, taking on the project has been quite challenging for the actor.

In The Beginning, Matt Smith Was Reluctant To Join House Of The Dragon

Even as showrunner Ryan Condal and Game of Thrones and A Song of Fire & Ice (the books that the new show is based on) author George R. R. Martin were putting the cast together for the show, the only actor they had in mind for Prince Daemon had always been Smith.

“Matt is really the only person we talked about,” Condal revealed. “We would say, ‘Like a Matt Smith or a Matt Smith type’ when talking about Daemon.”

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And as it turns out, Smith’s performance on The Crown was enough to convince Condal that he should play the role. Not to mention, the showrunner also found some parallels between Prince Philip and Prince Daemon.

“I just absolutely loved his work on The Crown as Prince Philip, who somewhat ironically is a similar character,” Condal explained. “He’s the second fiddle, in that case to the Queen of England, his own wife, and is a bit adrift. [Daemon] is similarly a bit of a rogue prince trying to find his footing and place in the world.”

And while Condal may have been convinced that Smith should get the part from the beginning, Smith himself was less inclined to take on the role at first.

“I was in a car park and my agent said, ‘There’s this part in this new show that is a prequel to Game of Thrones,’” the actor recalled.

“And I was like, ‘Ohhh. I don’t know. It’s a tough one, isn’t it? It’s a tough one to follow. Haven’t we seen this before?’ But then [the offer] sort of didn’t go away. Then it came up again, and then I went in for a screen test, and then that was that.”

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At the same time, Smith found himself drawn to Prince Daemon and the mystery that surrounds him.

“There’s a sort of folklore among Fire & Blood fans and Game of Thrones fans that when a Targaryen is born, you flip a coin. One side is greatness and the other side is madness, and you don’t know which side it’s going to land on,” the actor explained.

Matt Smith Says House Of The Dragon Is 'Really Draining' To Film

Onscreen, Smith’s Prince Daemon can be a menacing presence. He commands the City Watch. He wields the Valyrian steel sword Dark Sister and fights without reservation. And he rides and tames dragons just like his niece, Princess Rhaenyra Targaryen (Milly Alcock).

The role, clearly, has a lot of demands and that’s what made the work quite challenging, even for someone as experienced as Smith.

“There’s a lot of stunts involved, and that was challenging over quite a long period. It’s a big 10-month shoot,” the actor explained. “So physically, it was really draining.”

At one point, the stunts got so physical that Smith even got injured while on set.

“That was doing a stunt in a helmet,” he pointed out. “Hit the disc in my neck in Portugal. It’s a f****** pain in the neck — literally, metaphorically and physically.”

At the same time, the star also had to deal with scenes that required him to stay in character throughout multiple shooting days.

“But there are those big scenes where you sit around the table that are quite challenging because there’s so many characters to cover, and it takes days, and you’ve got to remain sharp and focused,” Smith explained.

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Luckily though, there wasn’t a lot of that to deal with, for Smith at least. “They’re often the ones that are hardest to shoot — the ones that can drive you bonkers,” the actor said. “I preferred being on a horse with a sword in the hand.”

As physically as his work on House of the Dragon may be though, there’s one part of the job that Smith can never complain about: riding the set’s dragon rig. “There was wind and rain, and it feels like a giant motorbike. It was fun,” the actor said of the work. “You’re quite high up. It’s not a bad day at the office.”

House of the Dragon has also been renewed for a second season, so fans can certainly expect to see more of Prince Daemon on and off his dragon.