welcome back to this special edition of "360 vanished." we want you to remind you of the phone number for the national center for missing and exploited children. 1-800-the-lost. it's not only children who can vanish without a trace, as we werekiore. michelle knight was an adult when she was taken, but because of that, she didn't get the same focus as amanda berry and gina dejesus. phoenix colton was 22 years old when she vanished. her parents will join us in a moment. but first, here is phoenix's story. it was only a week before christmas in 2011 when 23-year-old phoenix colton, got into her black chevy and drove away from her house in st. louis county, missouri. her parents thought she was just going to the store. but phoenix never came back. she's been missing a year and a half. >> she backed out of the driveway, and we never saw her again. >> three hours after phoenix drove off, her black chevy was