An actor who was unknown on the comedy scene until just weeks ago has scooped the UK's top comedy award, the Perrier.
Adamsdale's show has been described as "hilariously odd"
Will Adamsdale won the prize for the best rising star at Edinburgh's Fringe for his self-help satire Jackson's Way.
This is his first comedy show and he had planned to appear for just a week, playing to tiny audiences at first.
Then he got rave reviews, was described as "hilariously odd", and extended his run. Adamsdale, 30, also played Nigel Havers' son in BBC TV series Manchild.
"This extraordinary win has to be the ultimate Edinburgh Fringe fairy story," award director Nica Burns said.
His show was so strong it beat "a very strong shortlist" after getting among the main nominees instead of being shortlisted for best newcomer, she said.
"Only three weeks ago, he was an unknown playing to tiny audiences. He had to extend his scheduled run, is sold out and is now being hailed as a major discovery."
His competitors on the shortlist included Sarah Kendall - the first female to be nominated for nine years - plus Chris Addison, Reginald D Hunter and Epitaph.
Adamsdale plays Chris John Jackson, a motivational speaker who satirises the worlds of self-help and corporate jargon.
Jackson's formula for success is "Love x Property + Money = Gravy Train".
And the show, created at the Battersea Arts Centre, London, was only ever intended to be a work in progress to try out in front of an audience.
"If this is work in progress then I suspect the entire press corps won't have enough stars to award it when it arrives," The Scotsman's critic said.
RECENT PERRIER WINNERS
2003 - Demetri Martin
2002 - Daniel Kitson
2001 - Garth Marenghi
2000 - Rich Hall
1999 - Al Murray
"Jackson's Way is simply the best, funniest, cleverest miracle of make-believe on the Fringe."
Adamsdale will now have a £7,500 prize and the comedy world at his feet.
Last year's winner was US comic Demetri Martin and previous winners include Al Murray, Dylan Moran, The League of Gentlemen, Jenny Eclair and Steve Coogan.
Will Hodgson's show The Passion of the Hodgson won the best newcomer award.
A judging panel of 10 - including seven professionals and three members of the public - decided the shortlists and eventual winners.