48 Hours, known for a period of time as 48 Hours Investigates and 48 Hours Mystery, is an American documentary news magazine television show broadcast on CBS. The show has been broadcast on the network since January 19, 1988, in the United States. The show airs Saturdays at 10:00 p.m. Eastern and Pacific Time, as part of the network's placeholder Crimetime Saturday block; as such, it is currently one of only two remaining first-run prime time shows (excluding sports) airing Saturday nights on the major American broadcast television networks (along with Univision's Sabadazo). The show sometimes airs two-hour editions or two consecutive one-hour editions, depending on the subject involved or to serve as counterprogramming against other networks. Judy Tygard was named senior executive producer in January 2019, replacing Susan Zirinsky, who served as executive producer since 1996 until her early 2019 appointment as president of CBS News.

Reruns of 48 Hours are regularly broadcast on Investigation Discovery, the Oprah Winfrey Network and TLC as part of their daytime and/or weekend schedules, with varying titles based on the edition's subject matter (such as 48 Hours Hard Evidence, 48 Hours Investigates (a title that has also been used for the CBS broadcasts), 48 Hours on OWN or 48 Hours on ID).