I’m not sure when we stopped talking about The Gambler, the movie now on DVD and Blu-ray that we’re both here to promote, but somehow actress Brie Larson and I have spent the past five minutes or so talking about mushrooms and sex. I’ll admit that I don’t fully understand what we’re talking about (or why) but I’m transfixed, mostly because, whatever it is, Larson is talking about it so passionately. It makes no sense yet makes perfect sense at the same time. I normally don’t buy this hippie nonsense, but she’s so convincing and so genuine, by the time we’re done, I’m ready to join a commune and start making my own soap.

It’s this ability that has served Larson so well as one of Hollywood’s finest young actresses. She takes roles like those in The Gambler, which her own director readily admitted was “underwritten”, and spins gold. She’s one mega-franchise away from Jennifer Lawrence superstardom.

For her part, Larson disagrees with Gambler director Rupert Wyatt. “I heard he said [the role was underwritten], but I disagree. I actually think there are a lot of layers to Amy. She’s one of the strongest characters in the film.”

In the film she plays a genius-level student of Mark Wahlberg, an English professor who also happens to be a degenerate gambler. Wahlberg, who earlier in the year had starred in the bombastic Transformers: Age of Extinction, is not the first actor you think of when you think of “English professor” but Larson says the star brought his A-game.

“I came into read with him and instead of going over lines, he wanted to do his entire monologue from the classroom scene at the beginning of the film, which is something like 15 pages long. And he had the entire thing memorized. I was so impressed with how dedicated he was.”

Larson is no stranger to auditions. Last year she went on numerous auditions for Terminator: Genisys and almost had the part before Emilia Clarke was eventually cast (Larson was reportedly the favorite of the studio, Clarke the favorite of director Alan Taylor). She also revealed something she has never talked about: she was originally cast in Bridesmaids.

Producer Judd Apatow had seen her work in Scott Pilgrim vs. The World and brought her in for an audition. “But, Judd auditions aren’t like your usual auditions.” Instead of reading from prepared sides, actors were asked to instead create their own material. Larson was stumped. “I couldn’t think of anything. I wasn’t used to this at all. I sat in the waiting room, biting my nails and eating chocolate just wanting to bail. Just get up and leave.”

Instead, as she was being called in, she took her anxiety and used it. If she really didn’t want to be there, she was going to play that she really didn’t want to be “Somehow that worked,” she laughs. “They loved it. And I was cast in the film and they started to develop this character.” Larson was cast as a pregnant woman who gets into a fight with Kirsten Wiig at the airport, but as they began to workshop the script, the character was written out of the shooting script.

This might be a devastating blow for a young actress still trying to find her way (this was in 2010, two years before her breakout role in Short Term 12), but Larson never missed a beat. While she admits to sometimes getting down, she’s preternaturally...chill (it’s no wonder she’s close friends with Shailene Woodley). This is how we get on the topic of mushrooms and sex (I think). She recalibrates her existence by thinking of the natural beauty of the world and how, to reproduce, mushrooms burst and expel their spores into the wind in the hopes that they float the breeze in just the right way to find a compatible mate and — do you see how crazy this sounds? It all sounds so right. I’m listening in rapt, nodding my head. YES.

While Larson may have missed out on her chance at one Judd Apatow movie, she’s got another — Amy Schumer’s Trainwreck — opening this summer. And, it’s just the start of big things for Larson who actually gets excited to work in the studio system. For someone with the zen-like demeanor of Buddhist monk, she’s ready to kick some ass. “Put in a good work with the Star Wars people, will you?”

The Gambler is now available on VOD, DVD and Blu-ray.

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