Actor and now writer/director Paul Dano, whose inaugural feature Wildlife is playing in theaters after nearly a year on the festival circuit, and his partner and Wildlife screenplay collaborator Zoe Kazan like haunting thrift stores. They rifle through the bins of old family photos, pictures once so dear and now fallen into anonymity, and have built up a collection.

“I just find them incredible, to look at somebody standing outside of their home in 1950-something,” says Dano during a visit to the Bay Area where Wildlife screened and he was feted by the Mill Valley Film Festival. “These are all lives.”

Old photos, in a way, are a key to Dano’s adaptation of Richard Ford’s 1990 novel about a woman’s life crisis and a family falling apart in 1960 Montana. If he was going to make a movie out of the story in which teenage Joe watches helplessly as his father Jerry deserts the family to fight a wildfire and his mother vents her frustration in untoward behavior that she flaunts before her son, Dano needed a way into the story. He found it in a single line in the book in which Joe mentions that he’s taken a job in a camera store.

“That’s when I finally actually decided to write the film,” he says. “I don’t know why, but I was daydreaming. I was really turning over the film in my head for a long time, because I didn’t want to write to Richard Ford. I didn’t want to spend money on an option. I was like, ‘I want to make sure I can do it.’”

After writing a first draft, he handed his work to Kazan, already an accomplished playwright and screenwriter. She wrote the next draft and they continued to hone the work for the next five years, writing between acting jobs. The couple had Ford’s blessing to alter his story any way their film demanded, the writer telling Dano, “My book’s my book. Your picture’s your picture.”

Dano would go on to cast the couple’s friend Carey Mulligan—who had costarred with Kazan in a 2008 Broadway revival of Anton Chekhov’s The Seagull—as Jeanette, Dano’s Prisoners and Okja costar Jake Gyllenhaal as Jerry, and teenaged Australian actor Ed Oxenbould as Joe. What he was looking to create was a family, dysfunctional and maybe on the verge of breaking into pieces, but still a family.

“In the book there’s a lot of struggle, but there’s still a certain amount of compassion,” Dano says. “For me, with family, there’s so much love and there’s so much struggle and pain, too. The duality that both of those things are true—I was never looking to make a film that condemned these parents or make a film about bad parents. That’s not what it’s about to me. They’re people and I love them.”

Wildlife’s story begins, really, before Jerry has even left the family home to fight the fire when Jeanette takes a job as a swimming instructor. It’s a small gesture with big ramifications. Jeanette and Jerry married and had their child young. She has followed her husband from town to town as he tries and fails to find purchase in life, her disappointment growing. Getting a job is a first step toward independence for an unhappy housewife.

“She has a part of herself that’s been hidden or not attended to. There’s a crisis of identity happening and she probably doesn’t know her full self,” says Dano.

“I just found Jeanette to be so mysterious and complicated, and through the kid’s eyes, it reminded me of the mystery of who are parents are. That was true for me in a certain way, seeing your parents change or experiencing things you didn’t know they did at a certain age. You start to see that they’re human, that they mess up or they have problems.”

The story also explores the differences between the way people present themselves publicly and privately. The Jeanette people see shopping in town or as a swim teacher is different than the one Jerry and Joe see, and even they are only privy to what she allows them to see. They have no entry into Jeanette’s interior life. And while Wildlife is set in 1960, that is something that dichotomy between public and private remains true now, perhaps never more so.

“I find it so moving that we go into the grocery store, and say, ‘Hi,’ and smile with no clue—most of us have been through something,” Dano says. “I just find it beautiful that we’re these insanely layered—like the trees with their rings—and our rings are our emotions. I’m not on social media, but you look at all these people on something like Instagram, you’re seeing people present themselves as something, but there’s something else we’re not seeing. “

He adds, “There’s a passage in the book I think is part of really what spoke to me early on where Joe is watching his mom teach swim class and he’s thinking, ‘Oh, these other people are thinking, ‘Oh, there’s a pretty woman’ or ‘There’s a woman that’s happy’ or ‘There’s a woman with a good figure,’ but he kind of knows there’s something wrong. That duality, I don’t know, I find it incredibly beautiful and moving.” –Pam Grady

To read more about Wildlife, read my interview with Carey Mulligan in the San Francisco Chronicle.