One of the most prolific actors in the science fiction film Skylines' cast is James Cosmo, who has appeared in a ton of movies and TV series over his more than fifty years acting. In the film, Cosmo plays Grant, a wizened, paternal figure that provides the interstellar proceedings with a sense of much-needed heart amidst a devastating alien war.

In an exclusive interview with CBR, Cosmo discussed delving into his first major science fiction role with the film, the possibility of reprising his role as Farder Coram on His Dark Materials and starring on Game of Thrones as Jeor Mormont.

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What was it that first drew you to this project?

James Cosmo: When I was asked if I was interested, I just looked at the character of Grant, and it had some nice, little twists, and I liked the character, the strength of him, the loyalty. It seemed like a pretty cool character to play. There's not many action-y type parts that you're offered when you're my age, so I was really looking forward to it.

One of the things I love about your character is he's one of the most grounded in the entire ensemble, even with all these aliens around him. How was it finding that level of gravitas among the outlandish?

Cosmo: Yeah! I think who knows what Grant's early backstory was? Maybe he did live in a more grounded era. I think that's necessary to the audience to bring some semblance of reality and have someone with gravitas to move the story along.

Who did you really enjoy working with to develop this character?

Cosmos: Liam [O'Donnell], the director, obviously has a real hold on his vision, and so I really enjoyed talking with Liam, trying to bring what he created to life. That's what I really enjoyed. And killing aliens is great; it's great fun.

You've done a lot of fantasy and historical drama and grounded drama before. How was it leaning hard into science fiction for Skylines?

Cosmo: Well, that's one of the reasons that I wanted to do it, Sam, because I hadn't done anything hard science fiction. In another way, the story remains the same. Like Joseph Campbell said, there's only about eight true stories. You can take any story and take it down to its beginnings. Although it has some fantasy and fiction, it has to be based on truth, and the performance has to be based on truth so you're just putting your performance into an extraordinary world, and that's terrific. I loved doing that.

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How was it filming on location in Lithuania?

Cosmo: It's extraordinary! For so long, it's been under the shadow of communism. We never got to see what a magnificently beautiful country it is. And really, really nice people, fabulous architecture where we were. And a blazing hot summer! It was extraordinarily beautiful, only blighted by the horrible camp that we created. [Laughs]

I spoke with Liam and the cast earlier and they said they worked really closely to develop their characters. What are you most proud about getting to put your own stamp on Grant and the film overall?

Cosmo: It's nice when, hopefully, people can come back and say, "He was really believable. He had some attributes [that were] timeless, he faced difficulty with dignity and was resolute." All the human attributes that we admire, even in these strange circumstances, he's still there, he's still the guy. It's really heroic, in a way, that you imagine that nothing would change him; the things he believed, he believed and that was it.

Just to pivot a bit, it was just announced that His Dark Materials was renewed for a third season. I was wondering if you could speak to that experience.

Cosmo: Oh, I didn't know that! I really enjoy that show, especially working with Dafne [Keen]. She's a wonderful, young actress. The Gyptians weren't in the second season, so I haven't seen her in eighteen months or so. To see how much she's growing into a young woman was absolutely delightful, and I had great experience working with her. We've had some terrific directors working on it: Tom Hooper who was just a joy to work with. He's a real actor's director. I do hope I get asked back. You can never tell with adaptations and the Gyptians, but we'll wait and see. I'd love to go back.

RELATED: His Dark Materials Sets Up the Season's Final Showdown

In terms of HBO shows and HBO adaptations, you were on Game of Thrones. I'd be remiss if I didn't ask how it was appearing on that show as Jeor Mormont?

Jeor-Mormont-Game-of-Thrones

Cosmo: I have to say, Sam, I've worked for HBO a few times now. They seem to have a really uncanny sense of what makes great shows, and with Game of Thrones, you have to hand them credit to put their money where their mouth was when Dan Weiss and David Benioff told them they wanted to do this show; hugely expensive, never really been done on that scale for a television audience. And they backed them! And to be part of that and able to go on the sets...I've been on big movie sets a lot [and] this was just as big with as many people there and to realize that not only was our set working, but there were two other units -- one in Croatia and one in Morocco -- doing the same thing and putting it all together; my goodness, what a job!

But we didn't think it was going to be the phenomenon that it became. That was extraordinary! I remember meeting David and Dan when I was doing some ADR in Los Angeles after we had done the first season and said, "What do you think about another season?" and they just weren't sure. And then it hit the screens and look at that! So I was very pleased to contribute in small way to show, especially from the beginning.

Just to close it out, how has it been to dive headfirst into sci-fi and deliver this movie to audiences in this year of years?

Cosmo: Yeah, absolutely, Sam; year of years, my goodness. I think we desperately need some real entertainment and something to watch that takes us out of ourselves and makes for a really enjoyable watch, but at the same time, it applauds bravery and ability and strength, and that's what we need just now. And when all this is over, I hope they organize Skylines evenings and people sit down with an enormous bucket of popcorn, that you guys make in America, and watch all three films one right after the other. Even I would go to that! [Laughs]

Written, directed and produced by Liam O'Donnell, Skylines stars Lindsey Morgan, Jonathan Howard, Daniel Bernhardt, Rhona Mitra, James Cosmo and Alexander Siddig. The film is available now in select theaters, on demand and digital.

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