Everything you need to know about X Factor's Six Chair Challenge stage

The Six Chair Challenge sees the judges work on their own for the first time, choosing the six acts in their category they’ll take through to their Judges’ Houses (Simon has the Overs, Cheryl is the Groups, Rita takes the Girls and Nick gets the Boys). A singer can be given a chair, only to have it taken away if a better singer comes along. In some cases, a contestant that was swapped out earlier can be brought back in. Only those left sitting on the chairs at the end are safe. With a roaring crowd making their presence known, it’s nail-biting stuff.

Where is it?

After the bucolic delights of Boot Camp, it’s back to the SSE Wembley Arena where the (very vocal) crowd plays the part of the fifth judge.

When is it on?

This year's Six Chair Challenge takes places over three weekends. Due to the Rugby World Cup, X Factor will be broadcast on Sundays only for the first time ever. Each episode is two hours, airing between 7 and 9pm. Before the series began, Cowell promised the schedule change wouldn't affect the show. "We’ve made some changes to the format, I think it works," he told me. "The Sunday is going to work for us for about a month."

What are the crowd yelling?

You may notice members of the crowd holding their hands up to dictate a number, yelling ‘seat’ or ‘swap’ or ‘bring him/her back’. The judges really do look to the crowd for guidance and they don't hesitate to share their thoughts. Cowell dubbed it the “lion’s den” this year. Their roars were so loud he had to make a U-turn, apologising to an act as he reinstated him in a chair, very much at Wembley’s request.

If members of the crowd are holding up their fingers to indicate a number, that’s the singer they’re hoping will be swapped off of a chair in place of the act that has just performed. The other judges play along too, winding up the crowd to (teasingly) make life even harder for them. After all, they’re not a team any more; they’re competing to find the winner.

Expect drama

The acts find it tough, the judges find it tough, the crowd finds it tough… It’s a long process, with filming continuing long into the night. The crowd is replaced for the evening session, which revitalises the atmosphere. But it also means an act who’s already in a seat struggles to win over the new crowd when it comes to the swaps. And if Wembley isn’t behind you, it can seem bleak.

Good acts struggle

We’ve seen plenty of acts perform at Wembley for their first audition, shine during the group performance and wow during their second solo audition. But for some, the Six Chair Challenge bursts that bubble. Something doesn’t quite click. Or, your favourite is booted out (remember these nail-biting auditions?) and you vow not to watch the rest of the series…

… others stand out

Three auditions in, that singer you’d barely noticed comes into their own: picks the right song, the right outfit, the right moment to show the judges what they’re made of and then it’s smooth sailing through to Judges’ Houses. Think Fleur East does Uptown Funk – that's what the judges are looking for.

Cheryl wanted it banned

“I officially hate the Six Chair challenge,” Mrs CFV told me of the dreaded round.

Now an executive producer on the show, Cheryl admitted she’s lobbied for it to be axed.

“I’ve tried. I have tried,” she said, but nevertheless it’s back for a third series.

... and Grimmers is nervous

“Yeah! Cheryl came on my show last year when she’d just done it and she said it was terrifying and it was really, really, hard,” Grimshaw told me. But he's confident about his category, saying he has some "stars" among the boys.

What's next?

The travel lottery: the Judges' Houses locations are revealed. Whether Grimshaw really takes his group to Oldham remains to be seen, although history suggests we should expect Barbados, Las Vegas, New York and the like. This year this round was supposed to be broadcast live, but the logistics proved too tricky. So the auditions will be pre-recorded at the various locations as in previous years. However, in a new twist, the result will be announced in front of the acts' friends and families during a live episode back at Wembley.

Once the judges have their final teams, it's onto live shows and we can all start putting our Christmas decorations up...

The X Factor Six Chair Challenge starts Sunday 4th from 7:00pm on ITV