It’s not a bad gig when you are cast to play the on-screen love interest of Chris Pine. Just ask Holliday Grainger who portrays Miriam, the fiancé of real-life Coast Guard hero Bernie Webber, in Disney’s The Finest Hours. “It was really hard work trying to bring the idea of love to that situation,” says the actress, with a sarcastic giggle. “All the time I was trying to stop myself from smiling. I was like, ‘Stay in character! You can’t just grin at this.’”

Another thing that made Grainger happy on set was the fact that, unlike her sea-trekking co-stars, she was able to stay fairly warm and dry. And for those few scenes that involved her frolicking around without a coat in the Massachusetts snow, she had reinforcements tucked under her dress -- cropped long underwear and a heated vest. “I had a switch under my skirt so I could control the temperature. When it’s like 17-hour days till 7:00 in the morning, you gotta do something!” she exclaims.

We caught up with Grainger at The Finest Hours junket to discuss being wooed by her male-costar, wardrobe malfunctions, and why she loved being a part of Disney’s latest on-screen adventure.

First of all, tough gig having to be engaged to Chris Pine on screen…

Holliday Grainger: I know.

I mean how terrible was that?

Holliday Grainger: It was really hard work trying to bring the idea of love to that situation today. [laughs]

Holliday Grainger and Chris Pine in The Finest Hours

How was he as onscreen fiancé?

Holliday Grainger: He was great. He was really lovely to work with. I think that his portrayal of Bernie is just so incredibly sweet. I mean all the time I was trying to stop myself from smiling. I was like, “Stay in character. You can’t just…” [laughs] “You can’t just grin at this.”  But I mean he’s great working with because he has a confidence and an ease so that you really feel like we could do little bits of improvisation, or we quite often did lots of takes, so we tried lots of different ways. And that was…it’s always fun to play with something like that.

Your character is not on the boat having water thrown on your face the whole time, but you are running around in a dress in the middle of winter in Massachusetts.

Holliday Grainger: Yeah! I mean you can only put on so many layers underneath a dress that fitted. Also, it’s like when you have bear legs [laughs] there’s not much you can do. So it was pretty chilly. It was pretty chilly. I’m not going to lie!

Did you have cropped long underwear under there?

Holliday Grainger: Yeah. In fact, I think they had to cut one little bit from the movie because you could see my leggings under my dress! [laughs] But yeah, I mean I had everything you could imagine shoved under that dress. I even had a heated vest. It was kind of like a cut down wetsuit with heated wires going through it. I had a little switch under my skirt so I could control the temperature.

Anything to prevent hypothermia, right?

Holliday Grainger: Yeah. Exactly. I mean when it’s like 17 hour days until like 7 o’clock in the morning you gotta do something! [laughs]

Chris Pine and Holliday Grainger in The Finest Hours

How fun was it to play in the 1950s and get to dress up and be in this world before Twitter and cell phones?

Holliday Grainger: I think there’s always something really special about doing something set in a different period, because you really can sort of open your mind and transport yourself to a different…not just a different character, but a different mindset. It feels like almost doing a different genre or something. And yeah, I love the fact that this couple really did meet on the phone. It’s like how would that happen nowadays? It’s like they spent months talking on the phone and getting to know each other properly without ever actually having seen each other. It’s the sweetest thing. It’s so sweet!

Tell me about playing this feisty, take charge woman. You are not afraid to just storm into The Coast Guard’s office and make demands.

Holliday Grainger: I think Miriam in this movie just has…it’s like a self assurity, I think. She’s got a self-confidence that I don’t think…when she’s storming into the Coast Guard office, I don’t think it’s even on her mind. It’s like what she’s thinking is: “I’m scared for my man. Why is no one doing anything about this?” It just seems so right to her to do that. I don’t think there’s a question about the conventions of the time or anything like that.

Lastly, what can audiences expect from The Finest Hours?

Holliday Grainger: You can expect adventure and savior. And it’s like this beautiful story of morals and values. It’s very humbling and life-affirming. Also, there’s a little love story involved as well. [laughs]

Little Chris Pine…

Holliday Grainger: Yeah! A little Chris Pine love story!

Thank you. I love the film. Great job.

NEXT: Casey Affleck Interview for The Finest Hours

The Finest Hours opens in theaters January 29, 2016.