The Tears songstress gave all of the celebrity guests a run for their money in the make-up department as she rocked a contour to end all contours, but it was her sparkly lips and matching pillar box red brows (we always knew she was a total trendsetter) that drew the most gasps.
Unlike Nathan Massey, Cara de la Hoyde and Danielle Armstrong, Louisa opted out of traditional Halloween face paints and went all sassy on us with glitter-drenched lips that caught the light whenever she turned - just gorgeous!
Now, Love Island's Olivia Buckland was also sporting a whole 'loada shimmer (if you're feeling daring, here's how you can copy her smackers) but Louisa managed to trump her with her crystallised brows!
How amazing are they? We can't stop staring!
As beauty-obsessives, Louisa's make-up was the very first thing we noticed but there was absolutely no way you could miss her raunchy outfit.
Like Olivia, Louisa slipped into a skin-tight bodysuit emblazoned with a slogan that read, 'Hey little fighter, things will get brighter,' and her bralet was studded with lots of little red roses.
The stunner accessorised with a pair of fishnet tights and patent red boots (oo-er!) and, as if they weren't eye-popping enough, she offset the look with a hefty fluffy red jacket which she wrapped around her shoulders.
She was surrounded by a whole hoard of celebrities during the evening, but it's safe to say she made the biggest splash! Go, Lou!
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