 Big Brother is a reality TV show broadcast on Channel 4, and S4C in Wales, in which a number of contestants live in an isolated house trying to avoid being evicted by the public with the aim of winning a large cash prize at the end of the run. It is based on the Big Brother series produced by Endemol. The show s name comes from George Orwell s 1949 novel Nineteen Eighty-Four, a dystopia in which Big Brother is the all-seeing leader. The main shows are hosted by Davina McCall and narrated by Marcus Bentley.