Beauty Crush: Jessica Alba Rocks a Daring Hair and Makeup Look

What a difference a day makes!

On Monday night Jessica Alba attended Glamour's 2011 Women of the Year Awards in NYC with a simple half-up hairstyle and pretty, yet predictable makeup.

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But when she arrived at the H&M for Versace star-studded bash on Tuesday, the 30-year-old mom-of-two gave onlookers a reason to do a double-take.

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She styled her shoulder-length hair into a tight, sleek pony that showed off her dramatic lipstick, full lashes and flawless complexion.

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The actress posed alongside Emma Roberts, Blake Lively and Selma Blair who all hit up the party in fun looks from the limited-edition collection.