Writers often have ambivalent feelings when their book are adapted for film.

They may enjoy the fame and fortune a movie can bring, but remain loathe to give up control over their creation. Some have famously hated the final adaptation.

But Justin Torres loves the film based on his debut novel We the Animals. That's because Torres worked closely with director Jeremiah Zagar.

Zagar is a documentary filmmaker, but he always wanted to direct a narrative feature film. For a long time, he just couldn't find the right story.

"And when I found Justin's book I knew it was the right one for me to tell," Zagar says. "And I knew I could tell it."

There was already some interest in the book from other (and better-financed) filmmakers. But Torres was worried about the way the material would be handled — until he met Zagar.

"I didn't want it to be, like, poverty porn or like a Lifetime domestic violence film," Torres says. "And he got that."

The novel is based on Torres's childhood in upstate New York. His parents — his dad is Puerto Rican, his mother white — moved there from the city to raise their three boys.

In both the book and the film, the parents have a passionate love for each other and their children, but the passion sometimes turns violent. Zagar says he instinctively understood this complex family dynamic.

"It dealt with familial love in a way that I had never seen on screen before, and in a way that was very close to the way my family dealt with love," Zagar says. "There was an intimacy and a brutality and a messiness and a joy that were all kind of wrapped together."

While the parents struggle to earn a living (he has trouble holding down a job, she works in a factory) the three boys race through life as a pack — with a wild, manic energy.

The three young boys who play the brothers had never acted before. Zagar says he worked with them for months before shooting to prepare them for their roles. Zagar drew on his own roots as a filmmaker to create a sense of realism on the screen.

"I decided we should just make it as if we were making a documentary," he says. "So everybody lived together. You know, the boys all slept in the same room. The parents lived together. And we did sleepovers at the house together. And we created an environment that felt as real as possible."

The conventional wisdom in the film business, Zagar says, is that authors should not be around when a film of their book is being made. But he wanted Torres on the set.

Torres was not only watching his book being made into a film — he was also watching another fictional transformation of his life. And while there are scenes of joy and exuberance, there are also some tough moments.

"There was one time where the makeup artist was painting a bruise onto one of the boys, and it had just been so long since I had seen a little boy with a bruise on his face," Torres says. "But it was something very familiar to me. And that was hard. That was hard."

As he took part in making the film, Torres realized that some things that worked on the page didn't work when translated into a visual medium.

"In the book, the father is violent with the mother, but he's also violent with the kids sometimes," Torres says. "But in the film, we shot a scene and it didn't make it into the film because you just — you kind of couldn't forgive the father after seeing that. And it was very important that you at least understand the father, that at least your compassion extends to his world and his frustration, and that you don't dismiss him as a monster."

After that fight, the father leaves home for a while, and the mother takes to her bed. The youngest son, Jonah, who is based on Torres himself, climbs into bed with her and reminds her it is his birthday.

Jonah keeps a journal where he writes after everyone has gone to sleep. He also draws pictures which are animated in the film — fanciful images that float across the screen. Jonah, Zagar says, is harboring a secret that makes him different from his brothers.

"He knows he's different," Zagar says. "And not only does he know that he's different sexually, but he processes the world differently. He's translating the story of the family. That's in his journal. And in the processing of what his family's going through, he's able to free himself from the gilded cage that they've sort of created."

We the Animals does feel very real, Torres says. But at the same time, he thinks there is something magical about it. A tough reality has been turned into a lyrical work of art — which is just what he had aimed for in his book.

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