In ‘All Her Fault,’ Sarah Snook Lives a Mother’s Worst Nightmare

An investigator into Milo’s disappearance, as played by End of Watch’s Michael Peña, who is the father of a child with a disability, serves a vital function to the story from a practical sense—but also a personal one for Gallagher. “My child has autism and is disabled, and a lot of that storyline came from my own life,” she tells VF. To play the parent of a child with such challenges meant casting someone as soulful as Peña. “Michael did a really, really great job of encapsulating the feeling of isolation. You’re not having the same experience as other parents. You’re not hitting the same milestones. You don’t have the same outlook for your child’s future,” she says. “You are on a lonely island. It might be an island full of tons and tons and tons of love, but it is a little lonely. Every time [Peña] walks on the screen, I kind of smile,” says Gallagher. “He just makes everything better that he’s in.”

Keeping a firm separation between work and life was key in keeping Snook’s own sanity as a first-time mother on All Her Fault, directed in part by 3 Body Problem’s Minkie Spiro and The Handmaid’s Tale’s Kate Dennis. “There was one moment where the director whispered in my ear to think of my daughter [during a scene],” says Snook. “I was like, ‘Nope, I’m out.’ It was a well-meaning direction, but if I’m thinking of that I go into a hypervigilant stress response: ‘We need to call the hospital. We need to call the police.’ Bringing in actual reality is less useful as a performer than using my imagination. But that’s just me: I see kids play and really believe that they are a dragon. I can access the same thing without thinking about my own daughter.”

With some time and distance from the emotionally charged experience, Snook has come to appreciate the level of difficulty that she and her costars rose to—particularly in the show’s propulsive conclusion. “The person with whom I’m in the revelation scene in the last episode really challenged themselves to go to a place that they’re not necessarily required to in other roles they’ve done,” she says cryptically. “They were so compelling and so fucking good—I’m excited for them.”