The ladies were joined by another friend, former Spice Girl Emma Bunton, who also opted for a hint of red with her outfit.
Earlier in the day, Nicole made it clear that she was excited to see her besties on Thursday evening, Tweeting: "I think I'm in for a spicy night with a little surprise surprise..."
Emma, 37, posted a picture of herself with TV presenter Holly, 32, and Nicole on her Twitter page, adding the caption: "The blonds! [sic]"
But it sounds like Emma, who presents the breakfast show with Jamie Theakston on Heart radio, left early, as it was just Holly and Nicole who moved on to posh hangout the Groucho Club later on.
Suddenly actress Sienna Miller, 31, turned up and the girlies were thrilled with the addition to their night.
Nicole, 38, later gushed: "I met the gorgeous Sienna Miller last night she's a top girl."
We love how much fun these ladies were having!
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