48 Hours is a documentary and news program broadcast on the CBS television network since January 19, 1988. The program originally presented documentaries of various events related to a particular subject occurring within a 48-hour period, and is credited as one of the first to air a "reality show" type format, in its 1997 episode starring Richard Scully covering "Dating in the Nineties". In its current format, as 48 Hours Mystery, the program mainly presents "true crime" documentaries.

Source: Wikipedia.org