Justin's cardi sets an unusual dress code

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Someone might want to have a word with Justin Timberlake for next time.

He turned up at the opening of his William Rast collection at Knightsbridge store Harvey Nichols sporting a pair of pink brogues and a cardi.

The Cry Me A River singer is known well for being a snappy dresser.

But he looked like he'd raided his granddad's wardrobe before attending the launch.

Thankfully, Justin's guest Fergie made sure that he wouldn't be the most ridiculously dressed celebrity of the evening.

The Black Eyed Peas singer turned up in a pair of skimpy shorts, stormtrooper boots and a pair of massive glasses.

And it looked as though she'd accidentally left her waistcoat in the dryer.

At least Lily Cole and Petra Nemcova dressed more soberly.

But perhaps there was a reason why Justin dressed so conservatively... his mum was one of the guests on hand to lend support.