Brie Larson didn't just walk onto the set of Room and start acting. Honestly, that’s a massive understatement. Before she ever stepped into that 10-by-10-foot garden shed—a space that would eventually define her career and win her an Oscar—she basically disappeared. For a month, she didn't leave her house. She stayed out of the sun. No phone. No friends. Just her and the silence of her own home.
She wanted to know what it felt like to have the outside world become a memory. It wasn't just some actor-y gimmick either.
The Brutal Preparation for Brie Larson in Room
When we talk about Brie Larson in Room, we’re talking about a level of commitment that's kinda terrifying. To play Joy "Ma" Newsome, a woman held captive for seven years, Larson worked with a trauma specialist named Dr. John Briere. She needed to understand how a brain literally re-wires itself to survive that kind of horror.
She learned that the mind shuts down awareness to protect itself.
It's pretty heavy stuff.
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But the physical part was just as intense. She worked with a trainer to reach 12% body fat. That’s athlete level, but the goal wasn't to look "fit" in a Hollywood way. It was to look lean, wiry, and exhausted—the look of someone who’s lived on scraps and survived on pure adrenaline. She stayed out of the sun for nearly seven months to get that specific, sickly pallor of someone who hasn't seen Vitamin D in years. She even stopped washing her face to let her skin look raw and real on camera.
Building a Backstory From Scratch
Larson actually wrote three separate journals as "Ma" before filming started.
- One for Ma at age 10.
- One for when she was 14.
- One for 17, right before she was abducted.
She wrote about childhood crushes, fights with her mom, and silly teenage drama. Why? Because she needed to know exactly what Ma had lost. She needed to feel the weight of those seven years in that shed not just as a "sentence," but as a theft of a whole life. Once she finished them, she handed the journals to the crew and never looked at them again. They were just... there. Part of the history.
Creating the Bond with Jacob Tremblay
The heart of the movie is the relationship between Ma and her son, Jack. Jacob Tremblay was only seven years old when they filmed. If that bond didn't feel real, the whole movie would have fallen apart. Period.
To make it work, they spent three weeks "rehearsing," which basically meant playing Lego. They spent hours in the actual "Room" set at Pinewood Studios in Toronto. They made the toys you see in the movie together. They drew pictures of each other. Larson became a sort of second mom/big sister figure on set, even handling his immediate needs like bathroom breaks or snacks.
It’s actually wild how much of a "safe space" they created. While the audience sees a claustrophobic prison, for Jacob and Brie, that set became a private playground where they could just be themselves between takes.
The Reality of the "Room" Set
The set itself was tiny. 10 feet by 10 feet. That’s it.
Director Lenny Abrahamson didn't use many "cheat" shots. Usually, in movies, they’ll pull a wall out to fit the camera, but here, the camera stayed inside the box. Sometimes the cameraman was literally in the bathtub or under the sink to get the shot.
Larson has said that the second half of the movie—the part where they actually get out—was actually harder to film. Why? Because that’s when the trauma actually "hits" the character. Inside the room, Ma is in survival mode. She’s a warrior for her son. But once she’s safe, the walls in her mind come down, and everything she’s been suppressing for seven years floods back in.
Why This Role Still Matters
It’s been over a decade since the film's release, but people still talk about Brie Larson in Room as a masterclass in empathy. She was broke a dozen times before this movie. She was stressing about money even while the film was in production.
Then everything changed.
The film premiered at Telluride and then blew up at TIFF (Toronto International Film Festival). Suddenly, this "indie girl" who used to be a pop star in the early 2000s (remember "She Said"?) was the frontrunner for every award in Hollywood. She swept the Golden Globes, the SAG Awards, and the BAFTAs before finally taking home the Oscar in 2016.
Actionable Insights from Larson's Process
If you're a creative or just a fan of the craft, there's a lot to take away from how this performance was built:
- Research the "Why": Larson didn't just act "sad"; she researched the neurobiology of trauma with an expert.
- Physicality informs Mentality: Changing her diet and staying out of the sun changed how she moved and felt, which bled into the performance.
- Micro-environments: Creating a real-world bond with her co-star through play made the on-screen intimacy feel effortless rather than forced.
- The "Brie vs. Ma" List: To stay sane, Larson kept a piece of paper with a line down the middle. One side said "Brie," the other said "Ma." She listed traits for each to make sure she didn't lose herself in the darkness of the role.
Ultimately, the success of the film wasn't about the tragedy. It was about the resilience. It's about a mother who managed to make a 10x10 shed feel like a whole universe for her son. And that's exactly why we're still talking about it today.
Next time you watch it, look at the way she looks at the skylight. That’s not just acting; that’s months of isolation and research manifesting in a single glance. If you haven't seen her follow-up work in Short Term 12, that’s usually the best place to go next to see where this raw style of acting actually started.