Internet sensation Susan Boyle, whose performance on Britain's Got Talent last month has been watched on YouTube by tens of millions of people and made her a global celebrity, returns to the competition on Sunday.

The 48-year-old from Scotland wowed the judges and then an army of Internet followers with her rendition of I Dreamed a Dream from Les Miserables on the hit talent-spotting television series.

Partly because her dowdy appearance and age did not fit in with people's idea of what a celebrity should be, Boyle was an instant Internet hit.

Television crews from around the world were soon camping outside her home and newspapers have dedicated countless pages of coverage of her and what she says about our celebrity-obsessed age.

Boyle has also appeared on U.S. chat shows hosted by Larry King and Oprah Winfrey.

A fan site dedicated to Boyle is titled Never judge a book by its cover, and during her first performance in April, Boyle overcame sniggering in the audience when she took to the stage before reducing many viewers to tears.

According to the British media, Boyle is up against acts including street dancers Diversity, Darth Vader impersonator Darth Jackson and belly dancer Julia Naidenko on Sunday's show, the first of five semi-finals.

Her meteoric rise to fame has made her the bookmakers' firm favorite to win Saturday's final. Two acts chosen by the judges and the public go through from each semi-final.

The winner will perform at the Royal Variety Show and receive a check for 100,000 pounds.

(Writing by Mike Collett-White; Editing by Jon Hemming)

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