Young Filmmaker Lives His ‘Fairy Tale’ at Sundance

“I feel like I’m in a fairy tale,” Sean Wang said to the sold-out crowd gathered at the Ray Theater in Park City, Utah, last month for his Sundance Film Festival debut.

Mr. Wang, a 29-year-old filmmaker, was dressed in a black suit and white Vans (a nod to his skateboarding roots). He grabbed his chest in a show of how fast his heart was beating as he introduced his film, “Didi.” It is a coming-of-age story about an angsty, insecure 13-year-old Taiwanese American boy trying to find his place in the world.

“I’m just going to take a few seconds to take this all in,” he said before snapping a photograph of the audience. The warm crowd included Mr. Wang’s family and friends, the film’s cast and crew, and a handful of potential buyers who have the power to transform his station in life from aspiring filmmaker to bona fide Hollywood director.

It has happened before. Luminaries like Steven Soderbergh, Quentin Tarantino, Damien Chazelle, Ava DuVernay and Lulu Wang all went from hopeful dreamers to actual filmmakers in part thanks to the Sundance Film Festival, which just concluded its 40th year.

Mr. Wang is familiar with that lineage and, it seems, has been preparing for his Sundance moment since he discovered Spike Jonze’s skater videos as a teenager before heading off to film school at the University of Southern California. While working on and off for Google Creative Lab, he made a series of short films that mined different aspects of his childhood.

He also participated in multiple Sundance programs, including one for filmmakers between the ages of 18 and 25, a screenwriters lab and a directors lab. Each helped him hone his script, a personal film that both honors his relationship with his mother and reimagines teen films like “Stand By Me” and “Eighth Grade” through the lens of a first-generation American growing up in the cultural melting pot that was Fremont, Calif., in 2007. (Didi is Mandarin for little brother and a term of endearment in Chinese culture.)

Now, after slogging away on his script for six years and finishing the film, Mr. Wang is taking his first steps into the spotlight thanks to Sundance. The moment coincided with promotion of his short film, “Nai Nai & Wài Pó,” about his two grandmothers. That film was recently nominated for an Oscar in the documentary short category and will soon become available on Disney+.

“It’s almost too much to fully process,” he said in an interview. “It’s really exciting, really surreal, nerve-racking for sure, but overall I feel good.”

Mr. Wang has already overcome some unlikely odds. His film was chosen from a pool of more than 4,000 entries. And it landed in Sundance’s U.S. dramatic competition, a category that has produced a slew of Oscar contenders, including “CODA” and “Minari.”

Before a film can be an awards-season contender, though — or even a film that general moviegoers can watch — it needs to find a buyer. And that’s what Mr. Wang was hoping for at Sundance.

At a panel featuring first-time filmmakers, Mr. Wang commiserated with other newcomers about to unveil their movies. Rather than talk business, the directors kept their focus on how they hoped audiences would react and how they had gotten their films made, many of them mystified that it happened at all.

“I’m going to get emotional if I talk too much,” Mr. Wang said when asked about the people who stood by his side during the filmmaking process. “I’m trying not to cry more than 10 times at this festival.”

Yet underlying all that gratitude was a low-grade anxiety: Would audiences and critics like the film, and would that be enough for a buyer to scoop it up and plan to distribute it?

Before the film’s debut, Mr. Wang and his producers sequestered themselves in a makeshift green room. “Didi” features a handful of first-time actors alongside more seasoned veterans like Izaac Wang (“Good Boys”), who plays Didi, and Joan Chen (“The Last Emperor”), who plays his mother. The team chose not to screen the film for any buyers ahead of time.

“We just really want to honor this experience and let the movie speak for itself,” the producer Carlos López Estrada said.

It was a decision that both added to the pressure of the moment and somehow preserved the feel of the film that Mr. Wang was desperate to protect.

“This movie needs to feel community-driven, like it’s coming from the ground up, and not from Hollywood coming into my hometown,” he said. “We did it successfully. My grandma could be in a movie alongside this ageless actress, and it all feels like the same world because we kept it at home.”

The reception at the film’s conclusion was raucous. The crowd gave the movie an enthusiastic standing ovation, and Mr. Wang once again wiped away tears while he soaked it all in.

Michelle Satter, the founding director of the Sundance Institute, was part of the crowd, cheering on her budding filmmaker just as she had notable directors including Ryan Coogler (“Black Panther”) and Chloé Zhao (“Nomadland”), who went from Sundance to the Oscars. Mr. Wang attended her directors lab just weeks before he began production on “Didi,” using the mountain setting in Utah to test out his two most complicated scenes.

“Sean is going to have an incredible career, and we totally believe in him,” Ms. Satter said before Mr. Wang whisked her away to meet his family.

“Thank you for supporting Sean,” Cynthia Lee, Mr. Wang’s mother, said tearfully to Ms. Satter. “As a mother, I appreciate you.”

Reviews started flooding in as the filmmaking team made its way to the after-party. The Hollywood Reporter called “Didi” “touching,” while Variety deemed it “fresh and funny.” IndieWire wrote that it conjured “a sense of time, place and texture that sets the funny, fleeting movie apart from the Sundance Festival coming-of-age film pack.”

The party was a lavish affair filled with Asian cuisine from the caterer Mama’s Night Market. The band Hellogoodbye, which performs in the film, played at the party, and Mr. Wang’s childhood bedroom, which was used in the film, was recreated in the lobby of the venue. The place was packed, and guests were being turned away. Mr. Wang was mobbed by adoring fans and excited colleagues. Outside Park City, he is still an unknown. But inside that room on that night, he was a superstar.

“The discoveries that are at Sundance this year feel very much akin to some of the really exciting discoveries of filmmakers and films from the past 20 years,” said Tom Quinn, the chief executive of the distributor Neon. “‘Didi’ fits that. It heralds the dawn of this incredible new filmmaker.”

Adding to the swirl of excitement was Mr. Wang’s Oscar nomination for his documentary about his grandmothers. He flew back from Utah to watch the early-morning nominations announcement with his family at his childhood home. When “Nai Nai & Wài Pó” was announced as the final nominee in the short film category, Mr. Wang buried his head in his grandma’s lap then fell to the floor.

“I will never get used to this,” he said later in an interview.

“Didi” ended up winning the prestigious Sundance audience award, a prize that in years past has gone to movies like “CODA” and “Whiplash.”

On Wednesday, Mr. Wang was back in his apartment in Los Angeles. The sun was shining and he was sporting a fresh haircut when Focus Features announced the purchase of worldwide rights to “Didi,” which it will probably release this summer in theaters, perhaps as an antidote to the blockbusters that normally consume theaters at that time.

It was an ending to a whirlwind adventure that many aspiring filmmakers can only dream about.

“There’s something about being in Park City, where all of the things that were happening to me didn’t feel real,” Mr. Wang said. “You’re in this snow globe of a place, and my attention was needed in so many places, every single second of every single day. To be back and then the news, it feels like, ‘Oh, wow, we really did that.’”