Yellowstone's Kelly Reilly Deep-Dives Into The Series And What It's Like Working With Kevin Costner - Exclusive Interview

Kelly Reilly has starred in the Robert Downey Jr.-led "Sherlock Holmes" films and on Season 2 of "True Detective," but she's probably best known for portraying Beth Dutton on the hit series "Yellowstone," whose fourth season is currently airing on the Paramount Network.

On "Yellowstone," Reilly runs wild as the feisty daughter of big cattle ranch owner John Dutton (Kevin Costner). A master manipulator and emotionally unstable, Beth is fiercely loyal to her father and has an on-again, off-again relationship with ranch foreman Rip Wheeler (Cole Hauser). At the end of Season 3, she was caught in an explosion from a mysterious package left at her office, part of a seemingly coordinated attack on the Dutton family that also affected other members of the close-knit clan. Thankfully, it was revealed in the Season 4 premiere that Beth and kin had all survived.

In an exclusive interview with Looper, Reilly went in-depth about what it's like working on "Yellowstone." She discussed having Costner as her dad and Hauser as her love interest, what she hopes to see in the upcoming "1883" prequel, and why she never wants to play another version of Beth again.

Kelly Reilly thinks playing Beth is equally 'fun, challenging, and terrifying'

Your "Yellowstone" character Beth is kind of a firecracker. What is the most fun thing about playing her?

Well, she's so brilliantly written. There's not a line that she says that I don't love. She's a bit of a fantasy of all the things that you want to say, but you'd never have the courage to say or do. So, there is an aspect of fantasy of when I read her like, I wish I could have a bit of Beth in me to be able to say some of those things ... and I get to be able to do that. So, to be able to do that and get to do it with all those great lines, it's just so satisfying. I love her so much. I've been playing her now for four years. She's become one of the dearest characters I've ever played. She feels very real to me. It's equal parts fun and equal parts deeply challenging and terrifying to play sometimes.

Now that we know she's alive and well, where does the character's storyline go this season? Can you give us any tidbits?

I can give you some. I'm having trouble talking about what's happening in the season without giving things away. So, forgive me if I'm a little bit vague. But I think she's pretty much set out in Episode 1 on a path of vengeance, and she needs to find out who planned this attack to destroy her family — and she's going to destroy them. I mean, that's what she says, anyway. So, we are going to watch her figure that out and what action she takes. She said what she's going to do, but does she end up doing it? And is Jamie responsible or not? There are all of these twists and turns in the season.

And the other aspect of it is, she's still trying to protect the ranch, which seems an endless quest. It seems everyone wants this piece of land, and she's the only one really fighting for it for her father. I think she's found that she's come up against — they all have — the most terrifying of enemies now. These people who are wanting to turn it into a resort. Just like she says, "Cover it in pavement, destroy it."

She also says, "My father's dream is my Alamo that I will die defending." And that's exactly her M.O. and exactly what she feels is her life's purpose, just to look after and protect her father's dream. Which you could say is misguided. But that's who she is. And you're seeing her torn in a million different directions of who she is and who she allows herself to be. It's an interesting journey. It's wild.

Kevin Costner is one of the 'nicest, most generous' actors

Kevin Costner is a big draw for the series. What's it like having him as your dad?

Well, we've been working together for four years now, he and I, and we have so many scenes together, so many days working together. He's honestly one of the nicest, most generous actors I've worked with. We get on so well and we have this real fun relationship. So, yeah, I mean, it's pretty wonderful. He's so incredible on the show. I really respect him as an actor and the work he's doing. I just love what he does. I could watch him all day. I'm learning a lot from him.

Piggybacking on that, has he taught you any life lessons or given you any industry tips that you'll take with you well past "Yellowstone?"

I think I'm a bit old for that. He doesn't sit me down and give me advice. No. I mean, not directly. But I pay attention to how he plays a scene and how he works through the scenes and how he holds his ground and his space. I admire that in him. I admire his stillness as an actor. It's things like that that he teaches me inadvertently. But no, he's not sitting me down, giving me lessons.

What about Cole Hauser? What's it like working so closely with him?

Oh, Cole's my buddy. We're such good friends. And, honestly, we're so lucky to have found each other. We get to go on this journey with these two incredible characters with each other. We're both really protective of them, and we're really passionate about the work. We're both at a point in our careers where we found roles that we could put our soul and heart into. We really feel blessed, both of us. We don't take it for granted. We share that. And we support each other and have fun. It's really lovely.

We trust each other. I've been married for ten years, and he's been married forever, and his wife's incredible and wonderful. We're all friends. So, it's like, there's a level of trust there that allows us to really go as far as we go into the work with one another because we're friends, and I think that's really special.

Were you a fan of series creator Taylor Sheridan before "Yellowstone?" If so, what was your favorite work by him and why?

Yes. In 2017, when I got offered "Yellowstone," he had just won Best Director at Cannes for "Wind River." I hadn't seen "Wind River" at that point. I had seen "Sicario" that he had written, which I loved, but I hadn't seen "Wind River" yet. But I did hear his speech, his thank you speech, when he won the award, and how he dedicated it to the Native Americans and how he spoke with such intelligence and grace about them. I knew where he was coming from because he's a real cowboy, as well. He has that devotion for the life of the cowboy. But he also is super-connected to the Native Americans and their history, and our history with them.

Because of that, I knew that this wasn't just going to be a cowboy show with no depth or heart. I knew that it was going to be a full story. So, I really admired him for that, telling their story.

Reilly gets inundated with requests to play 'badly written Beths'

Are you excited for the "Yellowstone" prequel, "1883?" What do you hope to see from it?

Oh, I can't wait, honestly. I saw the trailer alongside everybody else. I know all the people who are working on it, they're all the same crew. You have Ben Richardson, who is our original director of photography from the first season. You have Christina Voros, who's one of our main directors, also working on it. I mean, all the crew, all the hair and makeup, and all of these really talented people, going back to the beginning story of the Duttons.

I'm going to be watching, basically, Beth's ancestors and seeing the similarities of those characters and why they're fighting for this land so much. Why it means so much to John Dutton to protect it — because it's their lineage, and the lineage of the needs of Americans. To see the whole gamut of who we're fighting and what we're taking, what we're stealing and what we've won, and what belongs to who. There's such a vast amount of story.

It's got Sam Elliott in it, who I love so much. He's one of my favorite actors. So, I can't wait to see him. I just think it's going to just be one of those massively luscious westerns. I can't wait to see it.

You've played all sorts of roles across your career, but what is the one dream role you wish you could play, whether past, present, or future?

Oh, I never know until I read it, so I don't have a role that's in my head. I mean, I'm a theater actress, as well. It's where I began, at a theater in London. So, there's a lot of characters on stage I'd like to play one day. But I don't know. All I know is that when you're playing one type of character, you're kind of looking for something that is different and fresh.

Obviously, I play Beth and people like it. So, I'm inundated with very feisty, strong, violent-type women. I don't want to play that again, those badly written Beths. So, I stay away from them and instead am looking for the next role that takes me into different waters. I don't know what it is. I do a lot of work in Europe, obviously, as I'm from here. I'm in London right now. So, I just want to keep myself engaged and excited about the work I'm doing. I never really know what that is until I read it.

Season 4 of "Yellowstone" airs exclusively on the Paramount Network on Sunday nights.