Viggo Mortensen 'freaked out' before The Lord of the Rings shoot

Viggo Mortensen "freaked out" on his way to The Lord of the Rings shoot because he was a last-minute replacement and didn't know anything about the story.

Mortensen defined the role of heroic Aragorn in Peter Jackson's Oscar-winning retelling of J. R. R. Tolkien's famous fantasy novels.

However, the part was not originally his, with Stuart Townsend first drafted in to play Aragorn until Jackson changed his mind a few days into filming.

"Lord of the Rings was a case where I replaced an actor and they were already filming - not only filming, but they'd been rehearsing for months and learning all these skills they had to have for those movies - language skills, invented the Elvish, and swordplay, and horse riding, all this stuff," Mortensen recalled to Collider. "And I was kind of freaked out because I said yeah and I'm on the plane, on this 13-hour plane flight, and I'm looking at the book, which I had never read. But as I started looking at it, I was like, 'Well, there's something.'

"There's always something that you can draw on. I had read or been read to as a kid, stories about Vikings and Nordic sagas and stuff, and there was something there that was familiar."

Luckily for Mortensen, his first scenes were all action, meaning he could get his "feet wet" with the physical demands of the role before he had any talking sequences.

Admitting it wasn't ideal, the 60-year-old said his son Henry, who was 11 at the time, spurned him to say yes to the career-making role.

"And obviously I'm glad I did it," he smiled. "It opened a lot of doors for me, and we had a lot of fun making those three movies. But it's not ideal. I sometimes have said no because I'm not gonna be able to do justice to it."