Justin Bieber And Will.I.Am For The X Factor USA
Pop superstars confirmed for Judges' Houses episodes...
Marc Anthonyand Nick Jonas will be the other two special helpers for the show's judges as they whittle down their acts in preparation for the Live Shows.
It has not yet been revealed which guest mentor will be helping which of the show judges - although there has been a rumour that Biebs will be teamed up with LA Reid.
According to Digital Spy, there have been rumours that the contestants could be split into four age groups this year.
Former The X Factor USA judge Nicole Scherzinger has opened up about her terror when she was sent death threats over something that happened on the show last year.
Sympathising with The X Factor UK contestant Rylan Clark, she said: "It breaks my heart. I was very emotional last year. I had death threats on X Factor USA.
"It really frightened me when I got them so it upset me to hear Rylan had to go through that.
"It kind of ruined me and I told them I didn't wanna leave my room. I didn't know that people could conjure up such thoughts – so hateful."
The Mirror also reported that Nicole was sceptical about settling down in the UK for good.
She continued: "I'm very affected by the weather. Will the weather stop me living here? Yes.
"I have got Hawaiian blood so I don't like being cold."