Aubrey Plaza and Megan Park on Getting Justin Bieber’s Approval for Fantasy Scene in Sundance Comedy ‘My Old Ass’

The title alone was enough to convince Aubrey Plaza to appear in “My Old Ass,” an offbeat coming-of-age story that was warmly received during its premiere Saturday night at the Sundance Film Festival.

“It all just made sense to me,” Plaza told the sold-out crowd at the Eccles Theater in Park City, Utah. “‘My Old Ass,’ I was like, ‘Oh man.'”

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And when Plaza spent time with Megan Park, the film’s writer and director, and discovered her affinity for unusual means of transportation, Aubrey knew she had signed on to the perfect project. Park was sporting a life vest during their first Zoom meeting, a sign of her love of all things nautical.

“Megan is the only director I’ve ever worked with who Jet Skis to work,” Plaza said. Park also picked up Plaza in a paddle boat for their initial meeting. “She paddled over me,” Plaza recalled. “And I sat there for a while just staring at her, inching along. I was like, ‘What the? What have I got myself into?’ And [then] I felt like, ‘This is right.'”

In “My Old Ass,” Plaza shows up as the middle-age version of her college-bound self (Maisy Stella of the ABC drama “Nashville”). Their past and present meet-up is facilitated by a mushroom trip. It’s not the only moment where hallucinogens play an important role in the story. At a later moment, Stella’s character Elliott has another drug-fueled evening in which she imagines she’s on stage as Justin Bieber singing “One Less Lonely Girl” to an adoring crowd of tweens. Using that track in the film meant needing “the Biebs” to sign off.

“Once he gave us the go-ahead, we were thrilled,” Park said. “We leaned into it even more. Everybody was so game to play and have fun.”

Stella gushed, “Guys, Justin Bieber watched that. Justin Bieber was so ill.”

The audience seemed to be on board with the tale Park spins in “My Old Ass.” The nostalgic story, about time’s implacable progress and the universal desire to hold on to people and places in our lives before they slip away, drew laughs at well-honed jokes. Some audibly choked up at some of the more tender moments.

“I kept thinking about this idea: there was a time when you did something like play pretend with your friends, and then you just never did it again,” Park said. “That made me really emotional. I also wanted to immerse myself in a joyful film and something that made people feel nostalgic for an easier, simpler time in life. Because life can be hard and shitty sometimes. I wanted to have an escape.”

(Pictured: Aubrey Plaza, Megan Park and Maddie Ziegler at the “My Old Ass” premiere)

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