Mikelle Biggs
On January 2, 1999, 11-year-old Mikelle Biggs was waiting outside her Mesa, Arizona home for an ice cream truck. Her sister went inside to grab her coat. When she came back — less than two minutes later — Mikelle was gone. Her bicycle was lying in the road, one wheel still spinning.
Karlie Gusé
On the morning of October 13, 2018, 16-year-old Karlie Gusé walked out of her family's home in Chalfant Valley, California — without her phone, without her wallet, and without a coat. She hasn't been seen since.