Twenty-One was an American game show originally hosted by Jack Barry that aired on NBC from 1956 to 1958. Produced by Jack Barry-Dan Enright Productions, two contestants competed against each other in separate isolation booths, answering general-knowledge questions to earn 21 total points. The program became notorious when it was found to be rigged as part of the 1950s quiz show scandals, which nearly caused the demise of the entire genre in the wake of United States Senate investigations. The 1994 film Quiz Show is based on these events. A new version of the show aired on NBC in 2000 with Maury Povich as host. Gameplay Two contestants, typically a returning champion and a challenger, entered separate isolation booths and donned pairs of headphones. The arrangement of the booths and the studio lighting prevented the contestants from seeing or hearing each other or the audience. At any given moment during the game, one booth would be "open", meaning that the occupant could hear the host in the headphones and could speak using the booth's microphone. The other booth would be "closed", with its microphone disabled and the headphones playing music to prevent the contestant from hearing the game. After each question, sounds of laughter and applause were played through the headphones of the contestant in the closed booth in order to prevent him or her from learning the outcome of the opponent's turn. The game was played in rounds, with Barry announcing the category for each round as it was dispensed from a machine on his podium; there were over 100 possible categories. The challenger played first in each round, with his or her booth open and the champion's closed, and selected a point value from 1 to 11. Higher-value questions were more difficult, and questions often had several parts. If the challenger answered correctly, the points were added to his or her score; a miss subtracted the points, but the score could never go below zero. The challenger's booth was then closed and the champion's opened so that the champion could take a turn. Barry would not tell either contestant about the other's score or performance. The goal was to earn a total of 21 points. If the challenger reached this score first, his or her booth was left open to hear the champion's turn, but the challenger would be cautioned not to speak or give away any information.