Evan Jackson Leong needed an ending.

He had been following Jeremy Lin, then a professional basketball player for the New York Knicks, since Lin had been a star basketball player at Harvard.

Up until February 2012, the story had been about Lin's struggles to make it in the NBA as an Asian-American. He had been overlooked at every level of basketball. After winning a state championship in high school, he received no college offers, so he went to Harvard. After starring for the Crimson, he was overlooked by the NBA. When he finally caught on in the pros, he was nothing more than a benchwarmer.

Then, in February, everything changed. Lin became an overnight sensation, taking over at point guard for the Knicks and taking the world by storm. In a home game against the New Jersey Nets, Lin exploded for 25 points to lead the Knicks to a win. He would score at least 20 points in his next five games, all victories.

That's when someone came up with the phrase "Linsanity," which Leong uses as the title of his documentary, set to premiere on Jan. 20 at the Sundance Film Festival.

Now a member of the Houston Rockets, Lin is one of the most recognizable players in the entire NBA.

"February gave us an ending," Leong said. "We didn't have an ending. It was a sad story up to that point."

Nevertheless, Leong said he believes it still would have been a worthwhile endeavor had "Linsanity" never captured the country's heart.

"I thought it was a great story anyway," he said. "I was really fascinated by how he got to where he was well before February."

As a fellow Asian-American, Leong related to Lin's struggles, but added that it was a story that had mass appeal.

"It's just a universal American story," he said. "He dreamed of playing in the NBA. He could have been a white kid or a black kid and it still would have been an amazing story."

But Lin did face some additional challenges and prejudices because of his heritage during his ascent to stardom, which Leong captured.

There was a stereotypical remark from Foxsports.com columnist Jason Whitlock on Twitter, along with an ESPN headline that read "Chink in the Armor."

"I think we all know racism is still here," he said. "What this did was really brought it out. Asian-Americans aren't the biggest minority in terms of media coverage."

Although both Leong and Lin shook off the prejudice without a problem, the making of the documentary faced other challenges.

Leong said there were times when he'd have to take on multiple jobs in interviews, often playing the roles of sound technician, lighting director, camera operator and interviewer at the same time.

"A lot of the time, it would just be me and Jer doing an interview - just talking for two hours," he said.

Leong also had to go to great lengths to find time to work on "Linsanity," since he had a full-time job to worry about. But, he added, it was a labor of love.

"This project is about passion," he said. "I worked on it on my vacation days from my day job. We were sleeping on couches to shoot this, but the goal was to get something we could share with the world."

Leong's documentary "Lisanity" will premiere on Jan. 20 at 2:30 p.m. at the PC MARC. It will also be shown on Jan. 22 at 8:30 a.m. in the Park City Library Theater, on Saturday, Jan. 26, at 6 p.m. at the Temple Theater in Park City and on Sunday, Jan. 27, at 6:30 p.m. at the Rose Wagner Center in Salt Lake City. For more information, visit www.sundance.org/festival