North East hiker Duncan Paylor fooled Jimmy Carr, Alison Hammond and Amanda Holden into thinking he could sing on BBC's I Can See Your Voice.
At first comedian Jimmy Carr joked that Duncan had "a mountain to climb" if he was going to convince the celebrity investigators that he could sing. But the passionate fundraiser managed to bluff his way to the end of the show and scoop the £10,000 prize.
Duncan, a security installation engineer, from Newcastle, was one of six contestants to take part in the gameshow, hosted by Paddy McGuinness, which aired on Saturday. He was joined by a tennis champion, a 999 call handler and a social media star, who were each investigated as players Tracy and Michelle tried to tell the difference between good and bad singers.
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Duncan was second to perform and within seconds he had convinced Amanda Holden he could sign, with Amanda telling investigators "that's 100% him" singing. And by the end of the show he was the last singer standing.
But it wasn't until Duncan performed Sorry Seems to Be the Hardest Word with Blue's Simon Webbe that it was revealed that he had been fooling everyone all along, resulting in a comedy collaboration and Duncan stealing the £10,000.
A message on screen at the end of the show read: "He might not be able to sing, but Duncan has completed five tough mudders, four great North runs, one marathon and ran 500 miles for charity."
I Can See Your Voice airs on Saturday, at 21:00 on BBC One and BBC iPlayer. Catch up on previous episodes on BBC iPlayer here.
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