Inside 'Catfish': A Tale of Twisted Cyber-Romance

Oct. 8, 2010— -- For Nev Schulman, a 24-year-old New York City photographer who became entangled in a twisted online love affair with the girl of his dreams, it all began innocently enough.

In 2007, Schulman was contacted by an 8-year-old girl named Abby on MySpace. A budding artist from the remote upper peninsula of Michigan, Abby said she'd seen one of Schulman's photographs published in a newspaper months before, and wanted permission to paint it. Weeks later, Schulman received a watercolor rendition of his photograph.

"I was kind of floored," he recalled, describing the young prodigy's work. "We all said, 'Wow, this is great!'"

Schulman sent Abby more of his photographs to paint. With her mother Angela's blessing, the two began to correspond online and Schulman developed a friendship with the entire family.

"I was in a weird place in my life where I didn't have a lot going on ... and it was very flattering," Schulman told "20/20's" Jay Schadler. "She was inspiring me and... it was a really strangely reciprocal kind of give and take."

Schulman was blown away to learn from Angela that local art dealers were bidding on Abby's paintings; one had sold for $7,000.

"It was just so satisfying to feel like I was contributing to some little girl's life," he said.

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Schulman was flooded with packages filled with Abby's drawings and paintings. That's when Schulman's brother Ariel and friend Henry Joost -- both filmmakers who shot Schulman and their friends hanging around all the time -- said they sensed a story was building.

"That's when I started filming because he would go, 'Pick these packages up, bring them down to the office and slice them open,'" said Ariel. "I thought it would make a cute short film. Simple as that."

The story would become the documentary film "Catfish," a reality thriller that shocked media and moviegoers alike when it premiered at the Sundance Film Festival.

Within two months, Schulman became Facebook friends with a small throng of Abby's fans, followers and family, including her 19-year-old half-sister Megan. Like Schulman, she was a photographer and he was intrigued by the striking photos of herself which she posted online.

"She was smoking hot, unbelievably sexy ... super beautiful," Schulman said.

Although they were complete strangers, he quickly fell for her.

"I was opening up to Megan in ways that I had not with actual girlfriends that I had had," he told "20/20."