STACK caught up with director Peter Hedges and the cast of powerful addiction drama Ben Is Back at the Toronto International Film Festival.

Ben Burns is a reformed teenaged drug addict who splits from rehab to spend Christmas with his family. What could possibly go wrong?

Once considered an early Oscar frontrunner – along with this season’s other addiction drama, Beautiful Boy starring Timothee Chalamet – both pictures and their stars have largely been locked out from major gongs.

Regardless, Peter Hedges’ Ben is Back is a gem of a drama offering a magnificent performance from Julia Roberts, who welcomes back her errant son Ben (Lucas Hedges) despite major concerns from her husband and daughter, portrayed by Courtney B. Vance and Kathryn Newton respectively.

Adding to the yuletide theme of foreboding, it’s no accident that mum and daughter are named Holly and Ivy.

When STACK meets with the cast at the Toronto International Film Festival, Roberts ponders the film’s ideas of unconditional love. “I don’t think that unconditional love is logical. I don’t think that there’s clarity. It doesn’t exist in those sort of compartments of thought,” says the mum-of-three.

Even more complicated, she muses, is the nature of forgiveness. “God, I don’t know, to say that makes it seems like everybody doing these awful things need to be forgiven all the time. I don’t know if that’s the case. I think it depends on the person. If you’re a forgiving person, you may be more open to that kind of ability to repair things and move forward. It’s a complicated emotion, forgiveness. Deeply complicated.”

As Ben’s less forgiving sister, Newton understands that it’s in the nature of youth to see things in black and white tones. “It’s really hard for Ivy to forgive him because she’s young. And when you’re young, you have to focus on yourself and she’s gotten her heart broken so many times that she doesn’t want to open it up again. So, him coming back is hard for her to accept, because she doesn’t trust him anymore. But it’s hard for her to fight her mom, because her unconditional love has been blindsided. So Ivy tries to be the voice of reason. But how can you have reason in this kind of situation?” she asks.

The film isn’t just a drama about addiction and how it tears apart families. It also wags a finger at pharmaceutical companies who profit from the misery of addiction.

For writer-director Peter Hedges – who cast his own son Lucas at the centre of the drama – Ben is Back is deeply personal. “Truthfully, the biggest influences on this were a phone call from a relative, saying that one of my relatives was in deep trouble and might not live,” says Hedges, who was wrestling with idea of making a film about addiction when Philip Seymour Hoffman died from an overdose in 2014. “It was such an untenable loss,” he says.

From that point on he began consuming himself with all aspects of addiction. “I watched every documentary, read every obituary – thousands of obituaries of people lined on my office walls,” says Hedges, who was finally propelled into action after Trump was elected.

“I asked myself, ‘What if I took all of this frustration and energy, and just put it into an original idea?’ I hadn’t written an original screenplay since Pieces of April, my favourite film I’ve ever made. I gave myself a narrow window, and turned off everything. I got off Facebook and I didn’t return phone calls, and just started writing.

“I knew pretty early on that this is the movie I’ve been waiting my whole life to make. If you came to me and said, ‘You can work for 20 more years, or you can make Ben is Back’, I would make Ben is Back, and be done.”

The process was hugely emotional. “I had a lot of self-doubt, but I find I have uncommon strength when I’m connected with whom and what I love. And I really believed in this story. Some people might think, ‘Oh, you wrote a movie for your son,’ but, no. I wrote a movie that I had to make. That’s all I did,” says the director, who’s son Lucas, 22, is already one of Hollywood’s most in-demand young stars, featuring in Boy Erased, Manchester by the Sea, Lady Bird and Three Billboards Outside Ebbing, Missouri.

Indeed, the man of the hour, and eponymous star of Ben is Back, couldn’t even attend TIFF, busy in rehearsal for his Broadway debut in a revival of Kenneth Lonergan’s play, The Waverly Gallery.

The director was stunned by his son’s careful study of Ben, a young man at the mercy of his addiction. “What I love and admire about Lucas as an actor is his internal life. He tends to it. And it’s so full. It’s very uncommon to find in an actor that age. That capacity to go, ‘I don’t have to prove to you that I’m a good actor’. He’s staggering as a talent. And staggering as a young man.”

Ben Is Back is in cinemas on January 31