Louis Tomlinson to Join Simon Cowell on X Factor to help mentor contestants.

The former X Factor contestant will return to help Judge Simon Cowell.

Simon Cowell Would Revive 'The X Factor US' to Find 'Great Groups

Louis Tomlinson 'being lined up to join the X Factor after Nick Grimshaw quits show' - Mirror Online

Simon Cowell gobsmacked as Louis Tomlinson hits back over X Factor songs

Louis Tomlinson Proudly Supports Simon Cowell at Star Unveiling

Simon Cowell addresses Louis Tomlinson's future as X Factor judge after his sister's tragic death

X Factor returns with 'most bizarre thing' Louis Tomlinson has seen on the show

Louis Tomlinson Part Ways With Simon Cowell's Syco Music Label

Robbie Williams, Ayda Field, Louis Tomlinson and Simon Cowell attending the X Factor photocall held at Somerset House, London Stock Photo - Alamy

X Factor 2016: Simon Cowell comforts Louis Tomlinson after performance, TV & Radio, Showbiz & TV

Louis Tomlinson Proudly Supports Simon Cowell at Star Unveiling