The American songstress is no stranger to making a splash, and she blew all of the other guests - including Paris Hilton and model Rosie Huntington-Whiteley - out of the water when she made an appearance in this elaborate, ruffly red rose-adorned number.
Katy oozed flamenco vibes as she sauntered past the paparazzi and that's when we realised that we'd spotted her oh-so-fancy frock somewhere before...
Anyone else think she looks uncannily like the dancing girl emoji?!
It wasn't long before Katy's traffic stopping red gown, that boasted ruffled cuffs, a lace overlay and scattered petals, set tongues wagging on Twitter and most people had the exact same idea!
One Twitter user wrote, "Katy Perry is the real life dancer emoji," while another joked, "Katy Perry stole her dress from the dancer girl emoji - and that's a fact."
Emoji comparisons aside, the Calirofnia Gurls looked sensational and she scraped her raven tresses back into a super-chic chignon bun that was fastened at the nape. She dialled up the glam factor with a heavy contour and a punchy red lip to match her eye-popping frock.
The stunner also rubbed shoulders with model of the moment Bella Hadid, Heidi Klum and Mischa Marton but it's safe to say she completely stole the show.
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