One of James Michael, Amelia Lily, 2 Shoes or Jonjo Kerr, who were all eliminated by the judges in the first week of the live shows, will replace axed singer Frankie Cocozza on Saturday's episode.
The public will now vote for James, Amelia, 2 Shoes and Jonjo for the first time. Whoever receives the most votes will win their place back in the competition from this weekend.
> Tell us which of the four acts you want to return to 'The X Factor'
An X Factor spokesperson said in a statement: "The four acts have never been in a public vote so, with Frankie leaving the competition, this is an opportunity for the public to decide who comes back to the show."
Voting details will be confirmed tomorrow (Thursday, November 10).
The X Factor's returning contestant will be revealed this Saturday at 8.15pm on ITV1.
> 'X Factor' Jonjo Kerr: 'Leave Frankie Cocozza alone'
> Gary Barlow: I'm hugely disappointed by Frankie Cocozza X Factor exit
> Kelly Rowland left speechless by 'X Factor' Frankie Cocozza axe: Video
> Frankie Cocozza 'X Factor' exit is incredible, says Olly Murs
Scroll through pictures of the four possible returnees and their X Factor journey so far below: