Twenty years later, Kimber Biggs still vividly recalls what she encountered on her Mesa, Arizona, street the day her older sister, 11-year-old Mikelle Biggs, vanished.
Kimber, 9 years old at the time, and Mikelle were playing outside just a few houses away from their own home in the twilight hour of Jan. 2, 1999, as the streetlamps began to flicker on around 6 p.m. Mikelle was riding her sister’s pink-and-white bike and carrying quarters given to her by their mother to meet the ice cream truck Mikelle heard approaching in the distance.
After getting chilly — and growing annoyed that Mikelle wouldn’t give up the two-wheeler — Kimber walked home, leaving her sister alone, she tells PEOPLE in this week’s issue.
Their mother, Tracy, sent Kimber right back out to fetch Mikelle as dinnertime approached. They hadn’t been apart for even two minutes.
“So I turned around and walked to the end of the driveway and I just yelled,” recalls Kimber, now 29. “I looked both ways down the road to see where she was riding, and I didn’t see her at all.”
“At this point it was kind of dusk,” she says, “and I looked down the road and I saw something in the road but I didn’t know what it was. So I started to walk toward it and realized it was my bike.”
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“At that point I didn’t totally know something was wrong,” Kimber says. “It was a very eerie feeling, almost Twilight Zone. It didn’t feel totally real.”
As Kimber drew closer to the bike that was left behind, “I noticed that the tire was still spinning.”
“That was the last time I saw her,” she says of her sister.
Police who later reconstructed Kimber’s steps concluded Mikelle was out of her sight for a virtual instant — launching an enduring mystery that is revisited in the latest episode of People Magazine Investigates, airing Monday night on Investigation Discovery. (An exclusive clip is above.)
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Authorities and family members have kept up their pursuit for answers, even as a leading suspect in the presumed abduction later was jailed for an unrelated crime and continues to deny any involvement in Mikelle’s case.
Kimber maintains a Facebook page, Justice for Mikelle Biggs, dedicated to the effort.
Says Jerry Gissel, a retired Mesa police investigator: “You never know when somebody is going to come forward with the information that’s going to solve this.”
People Magazine Investigates: Gone in 90 Seconds airs Monday (10 p.m. ET) on Investigation Discovery.