Shadow of Laci: Kristen Modaferri

July 22 -- Six years ago, Bob and Debbie Modaferri thought the mere mystery surrounding their daughter Kristen's disappearance would generate publicity and help them find out what happened to her. But they say it has worked against them.

"When you just have a disappearance-vanished into thin air [case], it doesn't have the same kind of appeal … at least as far as the media is concerned," Bob Modaferri told ABCNEWS' Primetime.

According to the Center for Missing Adults, there are more than 100,000 active missing persons cases nationwide. Oakland, Calif., police say they open an average of 10 new missing persons cases every day. In June 1997, Kristen Modaferri became one of those cases, and her disappearance remains one of the most baffling mysteries that most people have never heard about.

Kristen seemed to be excited about the life ahead of her when she vanished. The 18-year-old North Carolina State University student had earned a scholarship to study photography at the University of California at Berkeley. Kristen moved to California in the summer of 1997 and settled in a house with four male students in San Francisco. She started working in a coffee shop in the Crocker Galleria in downtown San Francisco as she prepared for her courses.

Unfortunately, Kristen disappeared the day before she was to begin her classes.

"I don't believe she's voluntarily missing. I don't believe she committed suicide," said Tim Hames, a private investigator who has been working on the case. "We have no victim, we have no witness. We don't have anything. She left us nothing to go on. I've looked at her bank records, Social Security number … there's nothing to indicate that she's alive or dead."

Last Seen at Work

The only thing investigators know for sure is that Modaferri worked at the coffee shop and punched out at 3 p.m. the day she disappeared. Some co-workers told investigators that they saw her shopping with a blond woman in the mall after work. Co-workers also remembered Modaferri asking about bus directions to a city beachfront called Land's End, which some friends had warned her was a dangerous hangout.