Three-year-old Madeleine McCann vanished from her parents' holiday apartment in Portugal on May 3, 2007. The young girl was left alone with her siblings, and has not been seen since. It's one of the most complicated criminal cases in history, with unreliable evidence, false leads, and new suspects.
In this gallery, we look back at one of the most publicized disappearances in recent history, and the recent leads that may provide answers after all these years. Click on for more.