Big Brother is a television reality game show based on an originally Dutch TV series of the same name created by producer John de Mol in 1997. The series follows a group of contestants, known as HouseGuests, who are living together in a custom-built home under constant surveillance. The HouseGuests are completely isolated from the outside world, and can have no communication with those not in the house. The contestants are competing for a $500,000 grand prize, with weekly competitions and evictions determining who will win the show. The series takes its name from the character in George Orwell's novel Nineteen Eighty-Four (1984). The series launched on July 5, 2000 to a successful start, though ratings and critical reaction continued to grow increasingly negative. This led to the second season being a revamp of the show, featuring a more competition-based challenge. The series has since continued to be a hit for CBS, and is the second longest-running adaptation of the series to date, after the Spanish adaptation.
The program is the first reality game show to air exclusively on a streaming platform with a season airing in the fall of 2016 on CBS's streaming service, CBS All Access. CBS also renewed the series for a 19th and 20th season. The 19th series is scheduled to premiere on June 28th 2017, while the 20th series is expected to air in the summer of 2018 .
The series was bought by CBS in early 2000 for an estimated $20 million. The United States version of the series officially premiered on July 5, 2000 when the original ten housemates entered the house. Since its inception, the show has been hosted by television personality Julie Chen. It is produced by Allison Grodner and Rich Meehan for Fly on the Wall Entertainment and Endemol Shine North America (formerly Endemol USA). The success of the series has spawned several spin-offs. The series airs once a year, during the Summer, with the exception of the ninth season which aired in Spring of 2008 and the Over the Top spinoff series broadcasting since Fall 2016. Currently, 18 seasons of the show have aired, with the 1st digital season currently under way. The show has aired a total of 545 episodes since it premiered, with the September 5, 2013 airing marking the 500th episode. To date, there have been a total of 253 HouseGuests compete in the series. Upon entering the house, the HouseGuests who leave the house without permission are not allowed to return. Should a HouseGuest break the rules set in the house, they can be expelled from the house. To date, there have been a total of four HouseGuests expelled from the house due to acts of violence and/or rule-breaking. There have only been two HouseGuests who have voluntarily left the game for reasons relating to personal matters.