Clearly keen to make a style statement, the Glee star turned more than a few heads in her racy red number, which was designed by Dolce & Gabbana.
The pricey frock featured a stunning lace overlay adorned with heaps of ruby gemstones, plus long sleeves and a demure below-the-knee hemline.
With such a gorgeous outfit Lea kept her footwear simple, opting for classic patent courts by Christian Louboutin complete with their signature red soles. Although we couldn't help noticing her heels did appear to be a tiny bit too big... oops!
She completed her look with a blue velvet clutch while sweeping her deep brunette locks into an elegant updo.
Lea was announced as a L'Oréal Paris brand ambassador back in September 2012, joining the likes of Beyoncé, Jennifer Lopez and Eva Longoria in uttering the brand's famous 'Because you're worth it' slogan.
And it seems she had a great time at the swanky event, later tweeting: "Thank you @LOrealParisUSA for the most incredible and inspiring night. I'm so beyond proud to be a part of the L'Oreal family."
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