So, who exactly are the mentors to look out for? Here are the most famous faces you might recognise…
Lewis is the winner of the third series of The X Factor, beating Ray Quinn in the 2006 final. She’s the second best-selling act (behind, of course, One Direction) to come out of the show.
Lewis will also appear as Ayda Field’s guest mentor.
He may have only finished runner-up in the 2009 series of American Idol, but Lambert has released three studio albums and ten hit singles. He’s now known for performing with band Queen as lead vocalist.
Lambert will also appear as Ayda Field’s guest mentor.
Starting his career as a session musician, Jackson’s big break came when he appeared on American Idol as a guest judge in the competition’s first series. He stayed on the show for 12 years before leaving in 2013.
Mostly known now for her judge appearances on American Idol and The X Factor US, Abdul started out as a dancer, choreographing music videos for the likes of Janet Jackson.
Warren is a multi-award-winning American songwriter who’s penned songs from Aerosmith’s I Don’t Want to Miss a Thing, to Lady Gaga’s Til It Happens To You.
Although a performer in his own right, Anka is also known for writing hits like This Is It with Michael Jackson, and Tom Jones classic She’s a Lady.
Real name Kenneth Edmonds, Babyface is a US R&B producer and artist who’s won 11 Grammy Awards.
Austin is a record producer who’s worked with performers such as Macy Gray, Sugababes, Anastacia and McFly.
A singer who hit fame in the 1980s, Sinitta later became better known for her TV appearances on the likes of I’m a Celebrity…Get Me Out of Here!.
X Factor fans will know this isn’t the first time Sinitta has appeared on the show, with the singer helping Cowell at the Judges’ Houses stage four times previously.
In a career spanning over 20 years, Stewart has produced tracks for artists such as Britney Spears, Usher, Beyoncé, Mariah Carey, Justin Bieber and Rihanna.
Seacrest is known to US audiences as the host of American Idol, a show he has fronted since 2002.
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