Linda’s son was shy, even as a baby. He didn’t play well with others. Not that he was mean; he just didn’t know how.

At age 13, he started a gaming profile to play fantasy games. Hearing him interact with other players over the headset made Linda happy. Middle school was hard for him. The family had moved. It was a new school. He was depressed. He was in and out of therapy because he hated it. All he wanted was to feel normal, but the therapy made him feel like he was “not human.”

Linda, played by Ann Dowd in the new film Mass, is sharing what she remembers about her son because Gail, played by Martha Plimpton has asked her to. “Why do I want to know about your son?” Gail says. “Because he killed mine.”

Written and directed by Fran Kranz, Mass is a volcanic, unflinching depiction of four parents navigating the unthinkable. Years before, Linda and Richard’s (Reed Birney) son opened fire on his classmates at his high school, before going to the library and taking his own life. Gail and Jay’s (Jason Isaacs) son was one of the victims.

Neither couple is certain what they’re after by participating in this meeting. Forgiveness? Acceptance? An explanation? Their lives are forever tethered. Maybe conversation can do something for their grief, the pain that has overwhelmed their lives in so many different ways.

“I knew I would do it, because how can you turn something as extraordinary as this down?” Dowd tells The Daily Beast. But she was concerned. “The other thought was: Can I live in this level of grief to the degree that would honor this character? We’re talking about something that is so profoundly painful and that so many parents have gone through. There’s a sense of genuine responsibility to get to the depth of this.”

Kranz was inspired to write Mass, in part, after the 2018 shooting at Marjory Stoneman Douglas High School in Parkland, Florida, where 17 students and staff members were killed. He was listening to an interview on the radio with one of the victims’ parents and became so overcome with emotion that he had to pull his car over and collect himself.

While researching more about school shootings and their aftermath, he discovered stories about parents of school shooters and parents of victims having meetings like the one he’d end up dramatizing in Mass. With titanic performances from Dowd and Plimpton, the fictionalized version of such a meeting becomes a rich backdrop for exploring what it means to be a mother—especially after such a loss—and how to persevere over grief on a journey toward healing.

Filming took place over two weeks in an Episcopal church just outside of Sun Valley, Idaho. Before it began, Dowd read A Mother’s Reckoning: Living in the Aftermath of Tragedy, the 2016 memoir from Sue Klebold, the mother of Dylan Klebold, who was one of the two shooters in the Columbine High School massacre of 1999. The book finds Klebold recalling what her son was like as a teenager. She wonders if there were signs that she had missed and works through what it’s like for a mother to grieve the loss of a child who had perpetrated such a hideous and violent act.

“Sue Klebold has gone through something unimaginable in its level of tragedy,” Dowd says. “It’s what Linda goes through. How would I put this…? I needed a friend. I needed to touch base internally with a woman who lived it and survived it.”

By contrast, Plimpton found herself avoiding those accounts. “I did not want to do any reading of that sort,” she tells The Daily Beast. “I just did not feel there was any way for me to approximate or conjure the world of Gail that would be helped by a real person’s experience. And I think I feared that it would add a level of detachment or removal that I did not want.”

What does someone like Gail want from a meeting like this, sitting face to face with the woman who raised the killer of her son? It’s almost too complicated to say. There are forces outside of her control that bring her there. Her marriage is falling apart. Her therapist wants her to go, specifically to deliver a statement to Linda’s face that the therapist thinks could free her.

“She’s being eaten alive by anger and recrimination,” Plimpton says. “I think she’s doing battle with herself, because she can’t conceive of saying the words that she’s supposed to say. Not in a million years. And I don’t think she can imagine that Linda will have anything to say that will fix it, that will answer her questions. But she can’t help asking.”

The meeting’s emotions undulate like readings on a Richter scale. There is politeness and pleasantries. Everyone smiles kindly and says thank you for meeting. There is small talk and sheepishness, as apologies are made for what attorneys had said publicly. Gail begins slightly begrudging and dismissive, but warms when she starts sharing stories about her son.

The gruesome details of the massacre are recounted. The idea of blame and culpability are explored. What it means to be a parent—to be a mother—is discussed, passionately. Everyone cries. Everyone yells. Everyone changes. As you watch, you wonder if, maybe, there’s a connection that is forged, parent to parent, over this morbid, involuntary bond they share.

“I think she simply becomes exhausted,” Plimpton says about Gail. “It hits critical mass. One of the things I think that human beings struggle with forgiveness is they think that if you do this or that, then you can forgive. Then you change your thinking, and then you can forget. Of course it’s not that way. Forgiveness is just the beginning, because you have to keep doing it. It’s a behavior. It’s not an action, and you keep going back and forth. It’s a process. It opens the door to a world that’s been unseen. That’s terrifying. That’s what we fear about it.”

Both actresses have understandable difficulty delivering clear answers about what happens in that room. It’s overwhelming. In some respects, the entire point of the meeting and this film is figuring out if clarity is even possible when things are that overwhelming, that seemingly impossible.

“All of us have experienced grief to some degree,” Dowd says. “This is to the exponential. But I remember in periods of my life when deep grief was present—I would say in the death of my father— the world changes. You are in your own world. Tragedy is everywhere you look, of course. But I remembered in my own experience that people are going about their business. They don’t realize the world has changed for you.”

Linda grapples with her own place within this extreme tragedy. It unmoors her. It means reconciling his actions with the person she thought she raised, who she thought she knew. It means coming to terms with the fact that she had to bury her son in secret. In place of proper mourning, there was shame.

Because of that, she wonders if she will ever be able to restore the memory of who he was, and if that’s even possible in a world where he caused so much pain. But what about her son? In one of the most powerful moments of the film, she says, “I know the world may have been better without him. I can’t say I would have been.”

For Dowd, the key to understanding that sentiment was when Linda says after, “Does that make sense?” Because, for her, it does. “Our children live in our souls,” she says. “They are part of us.”

Dowd’s oldest son is on the spectrum. “He taught me what listening was. And patience. That is the gift, among many other things, that that beautiful boy has shown me.” Then there’s her daughter. “She taught me what joy looks like, and lack of fear.” Her youngest, who is adopted and “came from a very difficult childhood,” continues to teach her everyday. “He’s taught me about trauma, what it looks and feels like. And that there is a way forward. Those are profound gifts.”

Linda resides in truth. She’s able to see that if her son had never been born, these children would be alive. These families’ lives wouldn’t have been ruined. There would not be so much despair.

“But Linda would not have been better for him not being there in this world, with her,” Dowd says. “I don’t know how that would be possible for a mother. Before I had children, I thought I knew what love was. I was raised in a loving home. I have a very loving husband. A child teaches you something else. It brings something else to you. I don’t even remember my life before my children. It just changes everything.”

Then she raises the big question that echoes through Mass—and one that Plimpton also asks frequently while talking about how these characters feel. She takes a pause and asks: “Does that make any sense?”