Interview: Brie Larson on navigating harrowing Room

As a former child actor, Brie Larson knew just how to coach her young co-star through their harrowing scenario

‘HOW crazy, right?” Brie Larson is laughing about Barack Obama. More specifically, the 26-year-old actress is marvelling at the fact that the President of the United States was spotted on holiday a few years ago buying a copy of Room, Emma Donoghue’s Man Booker-nominated novel upon which Larson’s latest film is based.

If the book’s subject matter is hardly the stuff of light holiday reading (it revolves around a five-year-old boy who has spent his entire life incarcerated in a tiny room alongside his abducted mother), the fact that it acquired a tacit presidential seal of approval should be enough to convince those who haven’t read it or weren’t aware of its impact upon publication that it’s a big deal.

Inevitably that makes the Golden Globe-nominated film something of a big deal too, burdened as it is not just by the weight of expectation, but also by the added responsibility of having to remain true to the novel’s unusual perspective without falling into the exploitation movie traps that could easily have ruined it (the book is told from the point of view of its young protagonist).

None of which unduly concerned Larson, who plays Ma to seven-year-old newcomer Jacob Tremblay’s Jack.

“By the time I had my first real conversation about it,” Larson explains, “the script that Emma had done of her book was with Lenny, and by the time I had spent five minutes with Lenny, I was sold.”

“Lenny” is Lenny Abrahamson, the acclaimed Irish filmmaker behind the Michael Fassbender-starring curio Frank. “He’s not someone that is interested in telling a true-crime-style, voyeuristic, exploitative abuse story,” continues Larson as she elaborates on the theme of the film. “He was interested in the humanity of it, the love that’s in it – the love that’s shared between this mother and her son. It’s about showing how the thing that’s worth living for can exist in a small space.”

The main conceit of the novel, and thus the film, is that titular location: an 11-by-11-foot room that functions as Jack’s whole world. The horrible truth behind his existence – that he’s a product of rape, that he and Ma are being held captive by a man who snatched Ma off the street seven years earlier and continues to abuse her on a regular basis – has been carefully hidden from him by his mother in a prolonged attempt to keep him psychologically healthy.

It hardly needs to be said that because Larson’s co-star is so young, the making of the film had to mimic its content. Abrahamson devised a version of the story that made sense to the boy, but also allowed the director to get the performance he needed. For Larson – who spent the three-week rehearsal period bonding with Jacob over Lego and being grilled by him about her favourite colour, her favourite animal and her favourite Ninja Turtle – it was also important to make Jacob feel like he was an equal creative partner.

“He wasn’t a kid we were trying to trick,” she says. “He was a creative force and he took it seriously in a way that was really fun for him. Even doing a crying scene – he liked being able to cry on camera without help from eye drops.”

It isn’t surprising Larson respected her co-star in this way. She got her start when she was his age, doing comedy skits on The Tonight Show With Jay Leno when she was seven. “I definitely recognised in him the drive and the passion I had for acting at that age,” she says.

Her own child-acting career continued with sitcom roles and bit parts in movies like 13 Going On 30, and she launched a short-lived pop career of at the age of 15 with the Avril Lavigne-esque Finally Out Of P.E. album in 2005. As an adult she subsequently began racking up small parts for the likes of Noah Baumbach (Greenberg) and Edgar Wright (Scott Pilgrim vs The World), and she had a starring role as Toni Colette’s daughter in the Diablo Cody-created/Steven Spielberg-produced cable show United States Of Tara. She also appeared alongside Jonah Hill and Channing Tatum in 21 Jump Street.

But it was really her starring role as a care worker in 2013’s acclaimed indie drama Short Term 12 that generated proper heat, earning her comparisons with Jennifer Lawrence and putting her at the top of Hollywood casting lists (she played Amy Schumer’s 
sister in Judd Apatow’s Trainwreck last year). Indeed it was that film which brought her to the attention of Abrahamson.

“Yeah, that was odd,” she says of the effect it had. “I always felt that everything was working and I was fine and it wasn’t until that movie came out where I felt, ‘Oh my gosh, there’s a whole other colour to this experience.’”

Her career is likely to be taken to the next level with Room. Her raw, committed performance has already earned her a Golden Globe nomination and it seems likely that an Oscar nod will follow in the New Year. She certainly put the work in: consulting a trauma specialist to figure out how Ma’s brain would function in survival mode, and working with a trainer and nutritionist to find a healthy way to replicate the wiry, Vitamin D-deprived state her character would be in after seven years of incarceration. “I felt that the only defence Ma had was her own body,” she says, explaining her lean, muscular appearance in the film. “She’d also constantly be on the move trying to wear out her son, who needs far more space than an 11-by-11-foot room.”

Having worked in such a contained way, though, her next film will take her to the opposite extreme: she’s starring opposite Tom Hiddleston and Samuel L Jackson in King Kong spin-off Skull Island, about which she can say nothing, confirming only that she’s filming it. Can she at least say whether say she’s playing an updated version of the Fay Wray role? She shakes her head and smiles. “That,” she demurs, “is a different movie.”

Twitter: @aliharkness

• Room is in cinemas from 15 January