The First 48

The First 48 is an American reality television show that airs on A&E. Set in several cities across the United States, it is based on homicide detective units solving cases, and focusing on the first 48 hours of the investigation, as the premise is alluded to in the title. The show is controversial, as it is focuses on real crimes and investigations, though it has been given incredible access to crime scenes, where news media does not have regular access. The First 48, is a reality show based on homicide detective units in various cities across the United States. The show's premise is summarized in its title voiceover: "For homicide detectives, the clock starts ticking the moment they are called. Their chance of solving a case is cut in half if they don't get a lead within the first 48 hours." A countdown timer is shown occasionally during the show to reinforce this, and to add drama.

Source: Wikipedia.org