Seventeen-year old Casey Crowder vanished early one Sunday morning after her car ran out of gas outside of Dumas, Ark. With no leads and no witnesses, investigators are desperate to find any CCTV cameras that can lead them to the missing teen.

Sian O'Callaghan disappears after a night out in Swindon, U.K. With the clock ticking, detectives pull hours of surveillance footage from the area and hit gold: footage of her getting into a taxi.