X Factor Final 2015: All you need to know

Chloe Best

As the three remaining X Factor contestants prepare themselves for the weekend's live finals, we've rounded up everything you need to know about the show, including the special guest performers and this year's winner's single...

When?

The first of this year's live finals will be broadcast from Wembley Arena at 8pm on Saturday 12 December. The three remaining contestants will go head-to-head, with one set to be eliminated at the end of the live show.

On Sunday evening the two remaining finalists will battle it out for first place in a two-hour show at 8pm, where they will have the opportunity to perform their version of the winner's single for the first time.

The Finalists:

Louisa Johnson

LouisaJohnson-

At 17, Louisa is the youngest contestant on the show and the bookies' favourite to win. Both Simon and Rita have said Louisa's rendition of James Bay's Let it Go is their favourite performance of the series, while Simon also said she is "potentially one of the best we have ever had" on the show.

Ché Chesterman

CheChesterman-

After facing Lauren in the sing-off in the semi-finals, Ché will be hoping to make it through to Sunday night's live finals. Cheryl Fernandez-Versini said that one of her favourite experiences on the show has been getting to know the "funny as hell" performer and tipped him as a "standout" singer in the competition.

Reggie 'N' Bollie

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Simon Cowell has admitted that he previously thought Reggie 'N' Bollie were "just a joke act" but he has been surprised by them throughout the competition. Their popularity with the public means they are ones to watch in the live finals, and could well be strong competitors to beat.

Guest performers:

The X Factor final guest performers have been announced, and it promises to be an incredible show. Former winner Leona Lewis revealed on Tuesday that she would be singing on Saturday night, promising that her performance will be "a bit of a surprise" as she won't be alone.

OneDirection-VIEW GALLERY

Coldplay and One Direction are also confirmed to perform, with the band returning to where their career began before they embark on a hiatus in 2016.

On Thursday it was announced after weeks of speculation that Adele will also be taking to the stage during Sunday night's show, while the 2014 winner Ben Haenow has confirmed he will perform his new single Slamming Doors on Saturday night.

He is not the only X Factor champion returning to the show; Little Mix have also revealed that they will be doing a "very special performance" with 2014 finalist Fleur East.

The winner's single:

The choice of this year's song is yet to be officially announced, but it is rumoured to be a cover of Bob Dylan's Forever Young. Simon Cowell has confirmed that 100% of all profits from the single will be donated to children's charities Shooting Star Chase and Together for Short Lives.

The song will be available to download immediately after this year's winner is crowned on Sunday 13 December.