By Lauren Huff
November 03, 2020 at 04:09 PM EST
Credit: Kimberley French/Focus Features

Diane Lane and Kevin Costner first teamed up to play Superman’s folks in 2013’s Man of Steel. Now they’ve reunited as a grieving couple determined to save their grandson at all costs in Let Him Go.

The thriller follows a retired sheriff, George Blackledge (Costner), and his wife, Martha (Lane), who are still grieving the death of their son when they embark on a trip to rescue their young grandson from the dangerous Weboy clan, who are living off the grid in the Dakotas. Things go from bad to worse when the Blackledges face off with the family, which is led by fierce matriarch Blanche Weboy (Lesley Manville).

Ahead of the film's release in theaters Friday, the two screen legends opened up to EW about working together again, the cost of doing the wrong thing for all the right reasons, and what they hope audiences take away from the movie.

ENTERTAINMENT WEEKLY: Why tackle the story of grandparents trying to rescue a child from dangerous isolationists?
DIANE LANE: I found it compelling that I wondered what I would do in this situation, because it was such a compelling concept that my character in the piece winds up having to do the wrong thing for all the right reasons. And being in that kind of emotional and mental state where you're compelled, and you're almost under the spell of trying to accomplish saving your loved one and your family. It's almost like there's no question that you're going to do what my character feels is the right thing, but of course that's open to interpretation, isn't it?
KEVIN COSTNER: There was something about the writing in this particular instance that I knew where the story was going right away. A lot of times that can be a bad thing, but in this instance it’s just a sense of dread that his wife, right or wrong, is taking him down a road that he knows is a bad path.

You’ve played a couple before. What do you enjoy about working with each other?
COSTNER: Well, number one, she's a world class actress, I think. She's one of the best that we've ever had. There's just no doubt about it. You can go to the Golden Age of Hollywood, and I would stack her up against any of the Barbara Stanwycks and the Hepburns. We felt like we only worked together for a minute on [Man of Steel], but the promise of what could be wasn't going to be extended in that particular movie, so this was an interesting way to circle back. And she's very dynamic in a very difficult role.
LANE: Kevin is a special human being. He has a genuine proof in his life and career and choices that he makes that he cares about and supports strong women. And you know, I can't say that about all movie stars. It's just a trait that is inherently noble and it's unspoken, but it's definitely present with him wherever he goes. It's inseparable.

Your characters are also coping with the death of their son. Talk about how that pushes them into this dangerous situation.
LANE: There is a shorthand that couples have with one another, in their understanding of one another, and you know when a battle is futile. Among longterm married relationships, there's a large demographic of people who will understand that he just wants to help his wife heal from the tragedy that they both experienced. And her access to that healing might just be the dangerous journey that he's willing to go on with her [to save their grandson]. It's really for her, because it's very hard to cohabitate with someone who is suffering from the effects of shock and grief and an inability to let go. Hence, the title.
COSTNER: The story highlights why we have to be careful with each other, because we can, through our own obsession, drag people into something that is a bad situation no matter how righteous we think our cause is.

Could you relate to how your character handled the disappearance of their grandson?
COSTNER: Yeah, every bit of it. Because if something's not true, I'll flag it. I just will. The writing of the situation was natural. It was very human, very honest. And that immediately makes it easier to play.
LANE: It's a tough call. Once you become a mother, all bets are off because this mammalian chemical thing happens to you where now your heart is walking around out of your body, in terms of your children and their children. The love and the connection that you feel is larger than your own life. It changes the framing of your existence. And it's something that you can hear about it all day, but then when you experience it, you're like, "Oh, this is what they were talking about." So I can relate to the desperate state of mind that [she's in], but one would never want to experience.

Kevin, your character is very stoic in the film — he's a man of few words. As an actor, did you find him more difficult to tap into because of that?
Well, it's not just about being quiet because you don't have all the words — it's about how you think when you're on screen. You know, even though it's not your quote-unquote turn to speak, it's how you live between the lines. That's how you listen. You know what's going to come out of her mouth, not because you know the script, but because you know her as a woman that you've lived with for 30 years, and that informs you. So, all those things are what I leaned on.

What do you hope audiences take away from the film?
I think the question of what would I do is enough of a compelling reason to watch a film. I mean, would you ever do the wrong things for the right reasons? How often have we done that and in what ways? And being confronted with such a direct assault of one's sense of purpose in life and duty — when somebody just removes that, do you go gently into that good night?

This interview has been edited for length and clarity.

A version of this story appears in the November issue of Entertainment Weekly, on newsstands now or available here. Don't forget to subscribe for more exclusive interviews and photos, only in EW.

Related content: