No spoilers here, but one of the big delights of Fast X (now playing in theaters!) comes in watching the movie’s small but memorable assembly of new characters find their specific landing spots in Dominic Toretto’s wild, wickedly fast world of family loyalty and revenge.

Alongside Jason Momoa’s deliciously demented new Fast X villain Dante, Fast Saga first-timer Brie Larson also enters the fray as franchise newcomer Tess, the daughter of MIA government spy agency chief, Mr. Nobody (played in earlier Fast & Furious installments by Kurt Russell). Tess breezes onto the scene as a seeming lone wolf, initially raising Dom’s suspicions before her life-on-the-line actions earn her the family’s full trust. Sporting a leather jacket scrawled with “Good Vibes Only” on the back, she’s good in a bar fight, good in a firefight, and — by the end of the movie — endearingly as good as her word.

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That kind of trust means more than money in Dom Toretto’s honor-bound code of loyalty, and getting Larson’s new character right meant enough to actor Vin Diesel (Toretto) in the film's early development that he even invited Larson over for family dinner — just to hash out how Tess should appear onscreen.

"Good Vibes Only" in the Diesel Household

Larson had long been pining to be a part of the Fast Saga, but actually landing the role quickly shifted her elation over joining the franchise to anxiety over living up to its high-flying expectations.

“When I got the phone call, I was dancing and screaming,” Larson confessed to interviewers on hand for the movie’s red carpet premiere in Rome. “I’ve been begging for years to be in these movies because I love them so much. But then I had this quiet moment where I was like, ‘I don’t know if I can do this. I don’t know if I’m worthy of this. Can I do anything that would honor this heritage and legacy and create something that’s meaningful and also additive to this?’ And I was lucky that pretty quickly, it was like within a day, Vin asked me to come over for dinner and I met his kids and his kids started grilling me about, ‘What will you be bringing to the Fast franchise?’

Even among family, that’s a pretty tough assignment to shoulder in your first days on the job. But Larson said Diesel’s passion for the franchise, as well as an aptly warm family reception over a shared meal, made short work of her worries and helped her shape Tess into the hero fans are finally getting to know in theaters.

“It was really intense and so for real and so helpful” to hash out Tess’ details in such a genuine and welcoming setting, said Larson. “They helped me with everything. His son Vincent was like, ‘We’ve gotta talk about your car.’ He pulled up all these tabs and was like, ‘This is what you’ve gotta do.’ And then his youngest daughter, Pauline, she was wearing this jacket that said, ‘Good Vibes Only’ and she was in this sassy mood, stomping around, and she’s just smart and blunt and funny. And I was like, ‘Okay, I’m gonna base my character off her.’ So that’s how Tess became who she is.”

That’s not just a throwaway anecdote, either: “Brie went to the wardrobe department and had them re-create the jacket,” as Diesel recently confirmed to Harper's Bazaar. “She wore it throughout the movie.”

Like we said at the start, no Fast X spoilers here… but from start to finish, Larson’s character ends up moving through one of the movie’s biggest emotional story arcs. Catch Tess and the rest of the extended Fast Saga family fighting the series' biggest nemesis yet in Fast X, now kicking up dust in theaters everywhere.

Need Fast X tickets? Get ‘em here!