Robbie and Gary have been in the music biz over 20 years – who they don’t know isn’t worth knowing. Robbie’s first star name collaboration was with Kylie Minogue on Number 2 single Kids. He followed that up with a duet with Hollywood megastar Nicole Kidman on Something Stupid – an Official Singles Chart Christmas Number 1. He even got to sing with his hero Frank Sinatra on his first swing album Swing When You’re Winning. On his new album Swings Both Ways, Robbie calls upon some of pop’s biggest names to share the stage with him: Lily Allen, Michael Bublé, Rufus Wainwright, Olly Murs and Kelly Clarkson all make guest appearances. Offstage, Robbie has never shied away from the A-list, dating famous ladies including Nicole Appleton and Rachel Turner and getting involved in a high-profile spat with Liam and Noel Gallagher. Gary’s got plenty of celebrity pals, but keeps a lower profile. Gary has collaborated with Andrew Lloyd-Webber, duetted with ABBA legend Agnetha Faltskog, sung with Michael Bublé (before Robbie did) and can count Elton John, Chris Martin and, of course, Robbie Williams among his mates.