Robbie Williams takes centre stage during his first appearance as a judge on the new series of The X Factor.

Robbie joins his wife Ayda, One Direction star Louis Tomlinson and head judge Simon Cowell on the new-look panel of the ITV series on Saturday, as viewers get their first taste of the show's audition stage.

The former Take That star will be seen getting up on stage to accompany singer Andy Hofton for a duet at London's Wembley Arena to perform an impromptu rendition of Robbie's solo hit Angels.

Viewers will also see Hofton perform a self-penned number called Castle of Love, which he reveals he offered to Robbie's former bandmate Gary Barlow.

Pop star Robbie is also left fighting back tears as he is transported back to a "messy" time in his life by American singer Janice Robinson.

Robinson, who had a hit in 1994 with Dreamer alongside Italian house duo Livin' Joy, returns to The X Factor for another shot at the big time.

In his first time as a judge on the singing show, Robbie pulls no punches while delivering his verdict on acts he is less than impressed by.

The 44-year-old tells one act that they have no identity, while commenting that another looks like they have come "to pay a parking fine".

X Factor boss Cowell, meanwhile, is visited by a ghost from his past when he is confronted by bar singer Danny Tetley from Bradford.

Tetley auditioned for Cowell's former show Pop Idol 17 years ago, but was rejected because of his appearance.

Tomlinson, who finished third on the show in 2010 with One Direction, receives some home comfort when 17-year-old Charlotte Lee reveals she studies at a college close to Tomlinson's old school in Doncaster.

Viewers will also be given a glimpse of Sunday's episode as the judges drive in together, singing along to Dolly Parton and One Direction, in which Robbie urges Ayda not to sing over 9 To 5 as she will "spoil it".

Tomlinson is seen sitting somewhat awkwardly next to Cowell, who plays one of his band's songs as they negotiate the drive-through at a fast food restaurant.

The X Factor returns for its 15th series at 8pm on Saturday on ITV, with the second episode airing on Sunday at 8pm.