SCROLL DOWN FOR VIDEO
We already know that Cheryl Fernandez-Versini will take the girls, Simon Cowell will take the over 25s, Louis Walsh will handle the groups, while Mel B mentors the boys, but in Friday's episode the judges will also discover their categories.
CLICK ON PICTURES FOR GALLERY
This week also sees the return of the dramatic six chair challenge. Each judge can choose a contestant to move to the chairs, but the contestant's spot is never safe until all the contestants have sang - and it looks like newlywed Cheryl has some tough decisions to make.
It's the first time Cheryl, Simon and Mel have experienced the challenge. Cheryl and Simon returned to the hit show this year for the first time since leaving in 2010, while this is former Spice Girl Mel's first time as a mentor.
"What's the worst thing that can happen?" asks Simon in the below video, released by ITV.
"You've got to say no to roughly ten or eleven sweet girls all dreaming of stardom, in front of 6000 people", he jokes, before Mel B adds: "That's daunting."
Robert Pattinson, Lizzie Pattinson.
The 31-year-old's performance and confidence impressed the judging panel during in-room auditions.
The male performers have been wooing the girls in the live auditions, and singers Jake Sims and Jake Quickenden have already found themselves on Mel's radar, with her telling Jake Quickenden: "You've got such commitment and passion."
Boy band Overload are also ones-to-watch as they got Cheryl clapping along to their original song during the live auditions.
The X Factor airs on ITV on Friday 26 September at 8pm