The former TOWIE star put on a pair of thick, black-rimmed glasses for the evening, pulling her hair back from her face in a tight pony and opting for vampy red lips to complete the look.
Lydia couldn't wait to party with her besties, including her sister Georgia, and tweeted: "Getting ready for tonight Geek Party with my bestes gals! x"
She then shared some snaps of the ladies' night online, adding that she and her friend Jem were the only ones in the group who had taken the theme seriously when it came to dressing up.
It must have been a good night for the star, who's been busy getting very festive of late, as the following morning Lydia complained: "My head hurts."
Ouch! We hope you're feeling better now, Lydia.
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