The judges started filming the second stage of auditions in front of arena audiences last week, and fans on the Digital Spy forums have already spotted some familiar faces among the series 10 contestants.
Boyband Rough Copy were one of the early favourites in last year's series, but were forced to pull out of the competition at the Judges' Houses stage due to visa issues.
Meanwhile, popular Scottish singer Jade Richards, who was a surprise departure from Judges' Houses in 2011 and a Boot Camp reject in 2012, is back for a third attempt to make the Live Shows.
Other returning singers from previous series include teacher John Adams, who appeared in 2011, and Joseph Whelan, whose axing at Boot Camp last year prompted a 200,000 strong Facebook campaign to get him back on the show.
John Adams on X Factor
Joseph Whelan on X Factor
Curtis Golden, who had a memorable audition in 2012 with his acoustic cover of 'Candyman', has also re-auditioned.
Digital Spy previously revealed that Melanie McCabe, Terry Winstanley and Amy Mottram would also be taking part in this year's series.
The X Factor will return to ITV later this year.
Watch the stars of X Factor talking to Digital Spy about series 10: