Nothing But the Truth is a British game show that aired on Sky1 and ran from 10 November 2007 to 26 March 2008.
It was based on the Colombian format Nada más que la verdad.
Prior to the show, contestants are asked to answer a series of questions while connected to a polygraph, but were not informed of the results.
A voice-over, or occasionally the host, announced whether the answer is "true" or "false", based on the result of the polygraph test before the show.
The contestant may stop before being asked another question and keep the money they have won so far; giving an answer deemed "false" forfeits the prize fund and ends the game.