Even among one of recent memory’s most star-studded casts, Mikey Madison’s role in Once Upon a Time In Hollywood was nothing if not memorable. After all, it was Madison as notorious Manson-girl doyenne Susan Atkins who said, as a pistol-shot to the film’s climactic bloodbath, “I say fuck ‘em, I say let’s cut their cocks off and make them eat it!” If a star wasn’t born then, it was when Madison’s Atkins meets her end via flamethrower at the hands of Leonardo DiCaprio’s Rick Dalton.

Madison’s reverence for Tarantino-style drama shines through the intense gore of that role. “[Tarantino] is a true artistic genius,” she says. “Working with him was wonderful.” Growing up in the San Fernando Valley, Madison studied Tarantino movies like other kids learn times tables, eventually taking her fandom to high-flying lengths. “Me and my dad ew to New York to see The Hateful Eight in 70mm,because we couldn’t get tickets in L.A.!”she says,pausing for a short laugh.“We had to see it like that.”

As a lucky charm, Madison kept that screening’s ticket stub while auditioning for and eventually shooting Once Upon. But she didn’t leave it all up to superstition: A self-professed flea-market devotee with an ear for Jimi Hendrix and The Mamas and The Papas, Madison took care with her first-audition look. “My first audition was with Quentin, [so] I came barefoot in my best vintage dress,” she recalls. In addition to seamlessly fitting into costume designer Arianne Phillips’s ’70s vision, Madison went one step further: “I [brought] a painting I’d made [while] in character, [based on one] that [Susan] had painted on an acid trip.”

However convincing Madison was as Atkins, her Tarantino debut may have raised eyebrows among fans of her longest held role. As the bratty and unfiltered high schooler Max on FX’s Better Things, Madison’s teen angst stops just short of murderous. “I think Max is the character that I’m least like…I like being really different from her,” says Madison, before conceding: “As I’ve grown into a woman, Max has [grown] as well.” Given her range of roles, it’s clear that Madison can grow in whichever direction she chooses.

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