The 12 remaining contestants, including Kitty Brucknell, Misha Bryan, Frankie Cocozza, The Risk and Janet Devlin, will be asked to show their "vulnerable" side by performing mellow and romantic tracks.
"The theme will allow contestants to show their more vulnerable side," a show insider told The Sun.
Saturday's live show will see the finalists facing the public vote for the first time, after four acts were eliminated by the judges last weekend.
The X Factor contestants will be covering Rose Royce's 'Wishing on a Star' for this year's charity single.
The X Factor continues on Saturday at 7.45pm on ITV1.
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