The mother-of-one attended the Marchesa autumn/winter '14 catwalk show, where she took her seat on the FROW alongside a whole host of stylish celebs.
Katie's gorgeous frock was designed by Marchesa (of course!) and featured a nude underlay with intricate red lace detailing.
The actress - who has her own clothing label, Holmes & Yang - matched her nails to her frock, adding chic nude heels by Christian Louboutin.
Clearly unfazed by the freezing weather conditions, Katie shunned the tights and went bare-legged for the occasion.
She did cover up in a crisp cream collarless coat, completing her expensive get-up with a dove grey Céline Trapeze bag (which we really, really want!)
The yummy mummy also struck a pose with her fellow fashionistas before the event, including Twilight's Anna Kendrick, American Horror Story actress Sarah Paulson and America's Next Top Model star Tyra Banks.
And earlier this week Katie stepped out at the Donna Karan show, where she spent time with 'Facemelt' singer Rita Ora.
Talk about an unlikely friendship, eh?
What do you think of Katie's dress? Let us know by commenting below as the best comment across the site each week wins £50!
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