Reveal went backstage at the arena auditions in Wembley and met some of the singing hopefuls. First up is 22-year-old Sophie Plumb.
Croydon singer Sophie welcomed her first baby earlier this year, but she's not new to The X Factor, as she previously auditioned in 2013.
"I auditioned two years ago but it just didn't work," she tells us. "My nerves got the better of me and I messed up. It was in the room and my breathing went.
"It was completely silent when I went in and I didn't know what to say. I started crying. It was ridiculous. I thought it was too real because I wanted it so much."
Soul and R&B singer Sophie, who also auditioned on Britain's Got Talent a few years ago, says she's nervous about singing in front of the judges.
"I'm just a full-time mum but I've been singing on the side. I feel anxious to see what the reaction's like. It's a challenge to sing in front of that much people."
Like many, Sophie is keen to impress music mogul Simon.
She says: "Simon, he's just the man! I need to impress him today. He's the one with the actual opinion."
What song will Sophie be singing at her audition?
"Well, now I've spoken to someone downstairs, they said Simon doesn't like slow songs. I was thinking of Adele's 'Make You Feel My Love' and I've switched it up into my own version. And I've got an acapella of The Jackson 5's version of 'Who's Loving You'."
Sophie is also worried about how the judges will be towards her. "I'm quite a deep thinker," she says. "When I come on stage I want them to get to know me straight away. I don't want to sing a song that doesn't mean anything to me."
Attending the auditions with her sister and two friends, Sophie adds: "I've been singing since I was six. I used to sing opera because my dad sang opera. I grew up around it. I try to sing a lot of up-to-date music, but my voice is just so soulful and deep."
So, would Sophie like to emulate the career of a former X Factor star?
"Leona Lewis is amazing," she says. "She did really well so I'd love to have the same success as her. I think I put myself down too much, but I like to keep it humble."
X Factor continues on Saturday (5 September) at 8.15pm and Sunday (6 September) at 7.45pm on ITV.
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