: The former One Direction member mentored the "Boys" and became the first former contestant to mentor a winner ( Dalton Harris ) . Robbie Williams : Mentored the "Groups" category .
: Finished as the runner-up under the mentorship of Simon Cowell. The X Factor UK - Season 15
: Robbie’s wife, who mentored the "Over 28s" category . 🎬 Key Highlights & Format : The former One Direction member mentored the
: Secured third place, marking a successful return after withdrawing from the previous season. ⚖️ The Judging Panel The 15th series introduced a brand-new panel, including: Simon Cowell : Mentored the "Girls" category. The X Factor UK - Season 15
: This was the final traditional series of the show before it transitioned into celebrity and "all-star" formats in 2019 and was eventually officially cancelled in 2021 .