The former TOWIE star oozed glamour in a dazzling gown from her own fashion boutique, Bella Sorella.
Her stunning frock featured a floor-skimming chiffon skirt and nipped-in waist, complete with a mesh bodice and sleeves adorned with glimmering sequins.
The dress retails at £279 so it's certainly an investment buy - but we're lusting over it all the same!
She let her sequins do the talking by keeping her accessories low-key, adding a simple cream clutch and black talons.
And Lydia was clearly pleased with her make-up look, posting this snap on Instagram along with the caption: "Ready for the ball :D"
She opted for perfectly groomed brows, thick liquid liner and pink glossy lips. To finish? Tons of false lashes, of course!
The fashion show marked the start of Breast Cancer Awareness Month, with other attendees including Victoria Pendleton, Gabriella Cilmi and host Denise Lewis OBE.
Lydia attended the event with her grandmother and mum Debbie, who looked equally chic in their sophisticated black frocks.
The pretty brunette Instagrammed this picture pre-show, adding the caption: "Three generations. Me, mum and nan en route to the Grosvenor House Hotel for @BCCare #theshow."
What a gorgeous family!
What do you think of Lydia's dress? Let us know by commenting below as the best comment across the site each week wins £50!