The award-winning documentary “One Child Nation” airs nationally Monday on PBS, and Utahns Brian and Longlan Stuy expect to be very busy starting on Tuesday.

The Lehi residents figure prominently in the film about China’s one-child policy, which, from 1979-2015, resulted in forced abortions, forced sterilizations and children being forcibly removed from their parents. (In Utah, it airs Tuesday at 11 p.m. on KUED-Ch. 7.) About 110,000 of those babies were adopted out to other countries; about 86,000 to American parents who never knew the truth about their children’s origins.

“In our research of which orphanages those children came from, a super majority of them came from agencies that had ethical lapses in their adoption program,” said Brian Stuy.

That’s the nice way of putting it. Adoptive parents were told the babies had been abandoned. But what really happened, tens of thousands of times, is Chinese family planning authorities confiscated babies from their families and sold them to orphanages, which would charge foreign parents up to $25,000 per adoption. And police, courts and various government officials were in on it.

Brian Stuy and his wife, Longlan (an immigrant from China) adopted three Chinese baby girls. For 10 years, Brian believed the story he was told by a woman who said she found his oldest daughter abandoned; the woman later admitted to Longlan it was fabricated by orphanage officials.

So the Stuys founded Research-China, which works to put birth families in contact with adoptees. They collect DNA from birth families in China and enter it into GEDmatch, a free database. “And then we just wait for the adoptees to be tested,” Brian Stuy said.

To date, they’ve collected DNA from more than 500 Chinese families and matched more than 60 of them with children who were taken from them and adopted in America. “It’s exhilarating,” he said.

Which is why they’re “absolutely looking forward” to “One Child Nation” airing on PBS, after a theatrical release and a run on Amazon Prime.

“I mean, the joy of being able to reunite a birth family with an adoptee — there’s nothing better than that,” Brian Stuy said. “It brings peace to the birth family. It brings knowledge and peace to the adoptee.

“There is, in a very real sense, in the heart of most adopted children, this hole. They wonder, ‘Why did my birth family leave me on the side of road?’ And to be able to fill that hole with knowledge is priceless.”

In almost every case, the stories of abandonment are lies. And it wasn’t just the adoptive parents who weren’t told the truth; neither were the birth parents.

(Leah Hogsten | Tribune file photo) Jialing Zhang, left, accepts the Sundance U.S. Grand Jury Prize for her documentary "One Child Nation" with Nanfu Wang during the awards ceremony for the 2019 Sundance Film Festival at the Basin Fieldhouse in Park City, Feb. 2, 2019.

“One Child Nation” — which premiered at the 2019 Sundance Film Festival and won the U.S. Grand Jury Prize: Documentary Award — features a 16-year-old girl whose twin sister was confiscated by Chinese authorities and adopted by Americans. The teenager tears up as she says she hopes her sister returns to China one day and is reunited with her family.

“The one-child policy is really … it took things way too far,” she says. “So many babies were taken away.”

The families were forced to give up their babies, and they were lied to about what would become of them. “When I talk to them,” said director Nanfu Wang, “you can see the pain on their face. And it’s something that stayed with them their whole life.”

“They all wonder if their daughter is still alive or where they might be. It’s really a struggle,” Longlan Stuy said.

For the Stuys, this is personal. “It started with our own daughter’s search,” Longlan Stuy said. They found their youngest daughter’s birth parents, whom they visited this past summer.

“It was an extremely interesting experience to meet her family and see the joy that they had,” Brian Stuy said. “Because they were told she’d come back when she was older. And if it hadn’t been for our tenacity to find them, she would never have come back.”

Since the documentary premiered, “We’ve received hundreds of emails from adoptees saying, ‘I just watched “One Child Nation.” I had no idea that this was even a possibility. Can you help me to reconnect and find my birth family?’” Brian Stuy said. “I’m sure we’re going to hear from a lot more after this is on PBS.”

And that’s the main reason the Stuys agreed to be part of “One Child Nation” — it legitimizes them in the eyes of skeptical adoptees.

“A lot of times, they’re, like, ‘What’s your angle? What’s the scam? Because I was told this would never happen,’” Brian Stuy said. “We have to convince the birth families that it’s not a scam, and then we have to convince the adoptees it’s not a scam.”

“This makes it much easier,” Longlan Stuy said. “Because if they know our name now, they reach out to us. It’s always easier than us reaching out to them. That makes so much difference.”