Housekeeper Relley C from Birmingham got four yeses back at the auditions in 2013 after singing for the judges, including current panellists Nicole Scherzinger, Sharon Osbourne and Louis Walsh.
She went on to make it through to judges' houses in the Girls category but was sent home by Nicole.
Tonight, Relley is back, this time in the Overs category with new mentor Sharon and she's the first to sing.
Relley tells cameras: "I was at Nicole's judges houses. We went to Antigua. Last time I got to judges houses I unfortunately didn't get through to live shows.
"I've grown up. Before I was on the show I was in the Girls, now I'm in the Overs. If I don't do it now, it'll probably never happen. If I fall again at the last hurdle I'll be devastated."
Relley sings Kelly Clarkson's Up To The Mountain for Sharon and her guest judge Robbie Williams.
And her emotional voice impresses Robbie, who says: "I was genuinely moved, I was genuinely transfixed. Whatever it is, she's got it."
Sharon reveals: "I was surprised three years ago when she didn't get through. She's never done a gig or anything like that."
Can Relley make it through to the live shows tonight?
The X Factor 2016 airs this evening at 7:30PM on ITV.