They might be ambitious, but they’re not out of their minds.

Hours before “August: Osage County” premiered Monday at the Toronto International Film Festival, director John Wells told the Variety Studio that when Tracy Letts’ Pulitzer Prize-winning play was being adapted for the screen, it was clearly a priority not to mess with its success.

“It’s a wonderful play,” Wells said, “and it’s a wonderful screenplay. It’s one of the seminal pieces of American dramatic literature over the last several decades. … We would have been crazy to try to significantly change what was so wonderful about it.”

So a main challenge in the the script was just managing its length without losing the lines cherished by those who saw it in the theater.

“Everybody could go down to Samuel French and buy a copy of the play, and everyone had their favorite lines that were no longer in the piece,” Wells said. “One of the things that happened immediately at the cast readthrough was that we picked up 10 pages by the next day, because everybody had their well-thumbed copy of the play. And about half of that ended up in the film, and some of it didn’t.”

Letts said that in theory, losing control of the adaptation was a risk, but he was not taken out of the equation.

“You’re always concerned,” Letts said. “Sometimes, it’s a bit of a dice roll, but fortunately I was dealing with people who cared what I had to say about it. So there was a lot of consultation and collaboration.”

Similarly, though there were all kinds of opportunities to shoot outdoors — and the movie does certainly offer an Oklahoma feel — things seemed to work best inside at the film’s home base — the family house.

“What informs so much of that play and that dynamic is to actually be in that house,” said Julianne Nicholson, who plays middle sister Ivy, who herself is a character defined by her choice when the play begins not to have broken free of where she grew up.

“I really loved to tell the story of someone who stays home,” she commented. “I feel the stories that are so often told are of the person who forges their way in the world and the adventures they have and how they get in trouble out there. I felt that sometimes (staying home) is a decision people make, too. You don’t always stay home because you don’t want to go, but (because) that there are reasons that keep you there … I just felt she was so interesting in exploring the relationship she has — it was fascinating, and terrifying.”

Nicholson was elated (and also terrified) by working alongside Meryl Streep, and quickly found herself in awe.

“Just being around Meryl is amazing,” Nicholson said. “Her craft, her skill, her magic is very real. I remember we were in the scene and she’s wearing these dark glasses, and the cameraman said, ‘You’ve got a fingerprint on your glasses. Can you get that off?’ The character she’s playing, she’s going to her husband’s funeral. She took off the glasses and just started putting more fingerprints on them. Any note she gets is just immediately filtered through who she’s playing.”

Having lived with the play for so long, Letts said that the premiere offered a new experience.

“I’m excited to see the play a hundred times with an audience,” Letts said. “I’ve never seen the film with an audience, so I’m excited to see how they react.”