250,000 people go missing every year in Britain including 100,000 children. The first 72 hours after someone is reported missing are the most vital. If you're not found within those three days, you may never be. This series follows the hunt for four missing people from the moment their family reports them missing, through the first 72 hours of the search, to a result. CCTV footage from the last sightings of the missing is used to try to locate them, alongside interviews with family and friends to give more information about where they could be.