The ad, which runs at three-and-a-half minutes and is believed to be the longest screened on British television, showed a "lost" piece of film from 1979 featuring Singleton talking about what might be happening in 25 years' time.
It appeared during last night's episode of 'Coronation Street', part of a £3.75m campaign to mark 25 years since McCain Oven Chips first appeared.
However, it has been revealed that the ad, created by TBWA\London's chairman Trevor Beattie, was a stunt, and that the "missing" footage had been shot earlier this year in Hemel Hempstead.
The elaborate stunt saw the Scarborough Evening News, the local newspaper for McCain's headquarters, run an advertisement asking if anyone had news about the missing promotional film.
The newspaper then reported that a local man had come forward with the footage, supposedly winning a prize of a year's worth of frozen chips.
Radio ads also appeared locally announcing that the footage had been found and that in it, startlingly accurate predictions about the future had been made. These include people listening to music on little silver discs, and a Russian billionaire buying Chelsea Football Club.
The stunt also saw hundreds of people in Valerie Singleton masks in Soho last week, celebrating the newly found film.
The ad was written by Beattie and art directed by Bill Bungay. It was directed by Duncan Z H Jones, better known as Zowie Bowie, son of David, through Frank Films, with post production by The Mill.
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