Louis Tomlinson came face-to-face with an 'X Factor' contestant who first auditioned with him in 2010, while filming this year's show.
Louis Tomlinson
The 'Back To You' singer has joined the show as a judge, eight years after he first applied for the show and went on to find worldwide fame with One Direction, and he was shocked when Tom Richards, who tried out at the same time as him, came back this year for another chance.
Greeting his old pal, who made it as far as Judges' Houses previously, Louis, 26, said: "Y'alright lad? I know ya! You auditioned the same year as me!"
While Louis and his bandmates - Harry Styles, Niall Horan, Liam Payne and Zayn Malik - went on to huge success, Tom did not make it to the live shows and has become a cruise ship performer.
He was also part of a 'Les Miserables' production on tour in Asia but is eager for another chance at a pop career.
A source told the Daily Star: "Louis and Tom were equals in 2010 and now they're worlds apart. Tom is hoping it will be second time lucky."
Meanwhile, Louis - who is mentoring the Boys category on the show -has admitted that working on the show has been "brutal", particularly the notorious Six Chair Challenge, which sees the contestants reduced to six per category and often sees hopefuls put through then replaced by other auditionees.
In an Instagram video, he said: "It was as brutal, if not more brutal, than you see on TV. Sitting there and experiencing it, I am nervous about my category tomorrow and excited and I hope everyone delivers."
Show producers have also changed up the Six Chair Challenge to introduce a new 'Golden X' buzzer.
Similar to the golden buzzer employed by the judges on 'Britain's Got Talent', the button will allow one person in each group to confirm their seat and a place in Judges' Houses.
A source previously said: "This year each of our judges has one Guaranteed Safe Seat to give away in this round.
"If the judge likes an act enough and they definitely want to see them at judges houses they'll press this golden X and give that act a Safe Seat.
"This means the act cannot be swapped out of their chair and they'll go straight through to Judges' Houses."
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