Guy Chambers’ ex-Westlife rescue mission spelt opportunity for his more famous writing partner. Robbie Williams had already been a star when he found Chambers, and what the songwriter brought him was structure, giving a young man the chance to turn his energy, charisma and occasional spite into a voice. The persona Robbie built was a restless, needy, paparazzi-era take on the classic British light entertainer, whose hits lurched between the wannabe traditional (“Something Stupid”) and the weirdly modern (“Rock DJ”), the painfully sincere (“Angels”) and the poisonously ironic (“Millennium”). He was the emblematic pop star of the early Blair years, and the Chambers collaboration underwrote his stardom, gave him the musical straight man his itchy impulses required.

And now he’s back, a few years on from that heyday, and two surprising things have happened. First, Robbie Williams is a veteran, hustling for position in a pop landscape tilted by reality TV. And second, Guy Chambers is nowhere to be seen – replacing him is Stephen Duffy.

Here’s where long-term UK pop observers might prick up their ears – Duffy is a character who’d been knocking around the fringes of British music since the late 70s, initially as part of a pre-fame Duran Duran, and then given heavy if slightly demeaning marketing in the mid-80s as “a guy who used to be in Duran Duran”. In which form he had a couple of small but well-turned hits, before switching direction as part of the bucolic Lilac Time. Later Duffy surfaced again, one of those 80s songwriters who found new admirers and impetus during Britpop – his most successful project in this phase being the one-off Me Me Me single, “Hangin’ Around”, with Alex James.

What Duffy lacked in success he made up for in sensibility – Robbie was taking up with a musical partner as magpie-eyed and mercurial as he was, whose only consistent traits were a solid melodic sensibility and a wryly detached attitude to whether or not anyone bought his records (On Duran Duran: “I certainly could have helped them become as big as Suicide”). Williams was keen to experiment; Duffy happy to indulge. The partnership, starting with “Radio”, was a commercial triumph, and reading Duffy’s interviews you feel he was surprised by that, and perhaps a little horrified.

“Radio” is not, by any wider standard, an experimental record, but it is a strange, invigorating one. It’s a Robbie Williams tune which draws on electroclash and stands comparison with the metapop of Richard X and Xenomania, but which also feels like the purest expression of Robbie-ness, his least compromised entertainment since “Rock DJ”. To the extent that it makes any sense at all – and that is not a very great extent – “Radio” sees Williams embrace and twist his unlikely elder statesman of pop role, declaiming his nonsense lines in a rich, stentorian tone as he plays a paranoid superstar in the process of losing his mind. Or maybe he doesn’t – the song switches tack halfway through to offer some cynical nostrums: “There are no surprises when nothing is expected”. Duffy and Williams’ working process was apparently ‘jamming at Rob’s house’ and “Radio” does nothing to belie that.

But if structure was the point, Williams could have stuck with Guy Chambers. The joy of “Radio” is in the performance, and in how much fun Robbie sounds like he’s having. He sounds liberated: there’s a devilish brio to his singing which was lacking as he plodded through lighter-waving ballads like “Eternity”. He’s not afraid to be ridiculous, delivering the word “RAY-di-OHHHHH” like a wizard casting a spell, or peppering the bridge with ominous mutterings of “Ouch. Ouch. Ouch.” His theatricality here reminds me of nobody so much as Billy McKenzie – perhaps Duffy had played a few old Rum Runner favourites.

On first play “Radio” feels like a curio: live with it and it reveals itself as Williams’ best Number One. And in a pop moment where almost everyone was playing miserably safe – “you will hear the songs you know”, indeed – even mild eccentricity feels worth celebrating.

Score: 7

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