The X Factor is back for a fourth series with the show's infamously harsh judges searching for the nation's next big pop singer.

Simon Cowell, Sharon Osbourne, Louis Walsh and this year's new judge, Dannii Minogue, have been holding open auditions across Britain and have directed their acerbic put-downs to an unprecedented 150,000 acts - from the tuneful to the talentless.

"We've had a reformed lap dancer, a woman who did impressions of a horse and two lads who performed their own song called Burger Flipper," said Simon, the creator of Pop Idol, Britain's Got Talent, America's Got Talent and American Idol.

As usual, the chosen acts are put into categories: Boys 14-24, Girls 14-24, 25 and Over, Groups. The judges are assigned a category and compete against each other as they train their acts for success in the live heats, which eventually go to a public vote.

The act with that indefinable 'x factor' will scoop a 1 million-pound recording contract, just like previous winners Shayne Ward and Leona Lewis. So far, every winner's first single has gone straight to number one.

Tension has been building among the judges as the new series approaches (well, it makes great television, doesn't it?). Simon has fired and re-hired Louis, while Dannii is, reportedly, already rowing with her new colleagues.

Louis said: "I'm hoping that I can wipe the smile off Simon's smug face and win another series."

Dermot O'Leary is the new host of X Factor, while Fearne 'The Royals' favourite' Cotton will take us behind the scenes in ITV2's The Xtra Factor.

With new presenters, a new judge and more applicants than ever, we will soon discover if the UK really does have a bottomless reservoir of talent...