In ‘Stillwater,’ Matt Damon is from a red state, and Abigail Breslin is 25

In Stillwater, Matt Damon stars as an Oklahoma oil field “roughneck” who finds himself in Marseille, privately investigating leads as he works to overturn the murder conviction of his grown daughter (Abigail Breslin), found guilty of stabbing her roommate.

He’s hopelessly out of his element until he finds a gig as a live-in handyman for a single mother (Camille Cottin) and her adorable child, who have him conversing in French in no time.

This language-absorption strategy works better for his character, Bill Baker, than it has for Damon himself. “I have been living with an Argentinian woman for 18 years, and my Spanish is … well, I’m not fluent. And she speaks perfect English. So that’s my fault.”

Damon refers to wife Luciana Barroso, with whom he has a blended family of four daughters, leaving him well prepared for the complex father-daughter dynamics in Stillwater (opening in theaters Friday and very distantly inspired by the Amanda Knox case).

Baker has failed his biological daughter, putting a redemptive spin to his protective and nurturing interaction with the little French girl in his care — played by Lilou Siauvaud, a screen natural whose work was immediately so good that Damon and director Tom McCarthy (Spotlight) rebuilt a good portion of the movie around her.

“The first day we shot, Tom and I sat down after everyone had left and said, ‘All right we’ve got lightning in a bottle here, like, what do we do? How do I keep this fun for her? And how do we keep people away from her?’ because there’s always the aunt or uncle who goes, like, ‘you should do this face,’ and they’re trying to help, but they usually infect the process,” he said.

They had an ally in Breslin, a former child star (she debuted in M. Night Shyamalan’s Signs), now 25, who made Siauvaud feel at home amid the hubbub of movie production.

“When I see somebody that age on set, I’m immediately protective of them. She’s so cute, and speaks no English, so I taught her how to say ‘I love my dog.’ Every day she’d run up and tell me, ‘I love my dog.’ I think she thinks that’s how Americans say hello,” Breslin joked.

Oscar-nominated Breslin (Little Miss Sunshine) and Oscar winner Damon (Good Will Hunting) have some tense prison-visit scenes together, as years of recrimination and neglect pass between them, mostly between the lines of dialogue.

“There’s no ego there. He just wants the movie to be as good as it can be,” said Breslin, who said Damon was happy to defer when the scene called for her to carry the emotional load. “He would say, ‘Just let me do my [essential shots], and you have the rest of the scene to do what you need to do,’ ” Breslin said.

The result is that Stillwater spends as much time mapping the psychological territory of father-daughter relationships as it does following Bill’s blunt-edged attempts to find evidence that will free his daughter.

“The people who are coming in expecting Liam Neeson to have a very specific skill set and start doing karate, they are going to be sorely disappointed,” Damon said.

Actually, Bill Baker does have a very specific set of skills, acquired over a very long career working with his hands, but they mainly make him good at fixing toilets and rewiring fuse boxes.

Which, if you’re a single mother moving into a crummy new apartment, is way more useful than martial arts.

Bill helps Cottin’s character with her flat and her child, and she helps him interface with the array of French cultures wherein clues to the true events surrounding his daughter’s case are concealed.

Driving Baker is the guilt at the estrangement that caused his daughter to leave Oklahoma and go all the way to France. That guilt was easy for Damon to locate. He’s now 50, and a father of four taking time off from movies to help his daughters reenter school this fall.

“Raising daughters helped me connect with the thought experiment of: What if I woke up and my daughter was 25 and in prison in a foreign country because I hadn’t been there for her, and I failed her in all these ways? It’s a nightmare scenario, and accessing that shame and grief was very easy, I think, because that is such a terrifying proposition for me.”

Only marginally less terrifying was accessing the world of Bill Baker, which meant going to Oklahoma (along with director McCarthy) and spending time with skeptical oil field workers.

He figured folks there would be familiar with movies like Saving Private Ryan and True Grit, but these hard hats knew Damon’s entire Hollywood liberal rap sheet.

“This guy drives up in his truck, and his job is to drive equipment out if the rig goes down, so he’s a really important part of the whole thing, and his life totally depends on the oil fields, just like the other guys. And his name is Big John. And all these guys are huge, and even next to them, he’s Big John, so you can imagine how big he is,” Damon said.

“And so someone says, ‘Big John, this is Matt Damon, he’s making a movie about our business.’ And Big John ambles over and says, ‘I hope to hell it’s better than that last movie he made about drilling.’ ”

Damon not only starred in the anti-fracking drama Promised Land, he wrote it (with friend and costar John Krasinski). The movie was shot in Pennsylvania, and inspired by events in Dimock, Pa.

“They were justifiably wary. Like, ‘What are you guys doing? What’s your angle here? Are you going to s— on us?’ ” Damon said.

McCarthy showed them his script, and explained the project in detail. “When they saw what we were doing — that we were just trying to make an accurate portrait of one of the guys — they could not have been more helpful,” Damon said.

Damon is a passionate environmentalist who donates to clean-water causes around the world and makes no apology for his creative role in Promised Land, or its concern for the potential effects of fracking on clean water.

Damon noted that he’s returned from Europe, where during the Cannes Film Festival Germany and Belgium were deluged with unprecedented volumes of rain, while back in the States the western forests continue to burn, sending clouds of smoke all the way to the East Coast.

Less drastic existential issues loom over the movie business. Stillwater was one of those movies filmed a few years ago and sidelined by pandemic delays. Now, as it opens, questions remain about the viability of the in-theater experience, and Damon’s movie is being perceived as a test of what the market will bear.

“I guess the answer is: I don’t know. I really don’t know. We’re going to learn a lot coming out of the pandemic, as we go through the next movie season. So much was affected by the pandemic, but the business had changed so incredibly before that occurred,” he said.

“This movie was so rare to be able to get made and to the market,” Damon said. “I worry. And I worry about the viewing habits of my kids’ generation. They are so used to controlling their content. They can pause it, they can stop it, they can talk while the movie is playing.

“Whereas when we grew up, it was more like going to church. You have to show up at this time and it will start with or without you. If you get up to go to the bathroom the movie does not stop. There are other people there, so you have to be quiet.

“You were there at the behest of the movie. Now, the movie is there at the behest of the viewer,” he said.

Or not, as time will tell.