1. PARDON HER FRENCH
Larson's real surname, Desaulniers, is French and the US actress grew up speaking French as her first language. She once said she used her great-grandmother's maiden name for her showbiz moniker instead, since it was easier to pronounce. She also chose it based on an American Girl doll she had as a little girl.
2. PRIVACY ISSUES
For her award-nominated role as a captive in her latest film Room, the 26-year-old chose not to speak to real-life kidnapping victims.
The drama, which opens here tomorrow, tells the story of Ma (Larson), who was abducted as a teenager and forced to live in a single room with her five-year-old son Jack.
"I was given videos of the very rare times these girls had done public interviews. They just broke my heart and made me so angry," Larson told The Hollywood Reporter.
"I'm a big believer in privacy. I didn't feel it was my place to invade their space. Ultimately, what the story is, is universal."
3. WORK COMMITMENT
Larson consulted nutritionists and lost weight until she had just 12 per cent body fat. She also stayed out of the sun for months so her skin remained pale, as it would have been after years of being locked away.
It's no wonder she told The Independent that being in Room was an "emotional marathon".
"I don't take roles that are 'just another role'. "I'm interested in learning more about myself and about humanity. So it should change you by the time it's done."
4. MOTHER AND SON
To bond with her on-screen son, played by nine-year-old newcomer Jacob Tremblay, Larson spent three weeks in Toronto with the young actor. They made arts and crafts, drew portraits of each other and danced to Mark Ronson's Uptown Funk on set to keep the mood light.
Ultimately, it was their shared love of Star Wars that sealed the deal.
"We went to a pizza parlour and he had these little Star Wars Lego figurines. I asked him some questions about Star Wars and once he knew that I could talk shop regarding Star Wars, then it was easy," Larson told Yahoo Movies.
5. CRITICAL DARLING
Room is set to be Larson's most critically successful film, earning her Bafta, Critics' Choice and Screen Actors Guild nominations for Best Actress and her first Golden Globe win earlier this week. She's also widely tipped to be nominated for an Oscar.
"It seems so far removed from my reality," she told The Telegraph.
"Even talking about it feels like planning your dream wedding when you don't have a boyfriend - there's just no point.
"I'm so thrilled that the movie is resonating with (audiences) and that is honestly all I could ever have hoped for."
This article was first published on January 13, 2016.
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