The Bodyshockers presenter looked incredibly demure as she ditched the skinny jeans and slouchy knits for this stunning black gown by Kolchagov Barba which boasted a square neckline, Victoriana-esque lace cap sleeves and a trailing hem that swept the red carpet as she walked.
She looks like a Hollywood screen siren, right? We love!
The mum-of-one flaunted her teeny tiny figure (we are SO heading to the gym this evening) in the curve-hugging number which she teamed with a simple yet totally chic boxy clutch bag and gold stud earrings to boot.
...but it was her gravity defying bouffant 'do that did most of the talking! Katie - who usually rocks her locks down - looked to hairdresser Megan Williams for her fabulous mussed up bun and 90s-esque fringe a la Girls Aloud's Sarah Harding, who also made her debut at the bash.
Katie rubbed shoulders with former Made In Chelsea star Ashley James, actor Ben Affleck and ex-TOWIE babe Ferne McCann (who left very little to the imagination) at the star studded central London premiere.
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