Lady Gaga Flashes Sheer Underwear in Slashed Dress

Leave it to Lady Gaga to go from a custom Chanel design to a racy underwear-revealing look in a matter of hours.

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Clad in a white tweed ball gown created especially for her by Karl Lagerfeld, the pop star, 25, made a grand entrance at the opening of her own "Gaga's Workshop" at Barney's New York on Monday.

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"Getting ready for the opening of GAGA'S WORKSHOP at BARNEY'S in NY tonight! Wearing custom CHANEL by Karl Lagerfeld. #PinchMeMom #OhEmGee Gaga tweeted before arriving at the ribbon-cutting.

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Later that evening, she changed into a black one-sleeve Stephane Rolland dress with a knee to thigh slit that showed off her sheer undies and unicorn tattoo for the International Emmy Awards.

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