The series name comes from the statistic that the odds of solving a case decrease by 50% if a solid lead is not found within the first 48 hours after the personhas gonemissing. Filmed in Chicago, the series gives an inside look at the real-life cases and procedures of the Chicago Missing Persons Unit. Similar to its predecessor series, The First 48, each episode usually focuses on two cases, beginning with the report of a missing person and ending with either a resolution or the point when the case reaches an extended dead end.