Louisa Johnson, Lauren Murray and Kiera Weathers have all made it to this final stage of the competition.
Tonight's opening theme is 'This Is Me' as each act gets the chance to show exactly what they represent and who they are as a performer.
Lauren, not too surprisingly, is repping for Whitney again and teased of her performance: "Wait till you see the set, you're going to die, it's so sick, honestly, it's so sick, trust me."
Kiera added: "I'm really excited but there are nerves for Saturday, I'm not going to lie. I found myself before [on the stage] like 'Is this really happening?' It's all so surreal, it's a lot to take in. It could change your life."
From this evening the girls will be joined by a fourth act after the judges decided to bring back Monica Michael to the competition as this year's wild card.
Mentor Rita said of the decision: "I couldn't sleep Sunday night thinking about Monica and if I could convince the other judges of giving her a wildcard.
"It's so great that Simon, Cheryl and Grimmy agreed. What a rollercoaster for Monica but sooo glad to have her back. So exciting."
Monica, who got as far as the six chair challenge last year, added: "I’m so hyped to be back as the wildcard. Thank you to all the Judges for believing in me and for the public for supporting me. See you on Saturday night!”
The X Factor live shows air this evening and Sunday night on ITV at 8PM with Little Mix, Ben Henow and Ellie Goudling on the bill of guest stars.
Browse pictures of the X Factor 2015 finalists - including new wild card act Monica Michael - below...