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Lady GaGa shocked fans at the U.K.'s Royal Variety Performance on Monday with a routine suspended high above the stage, despite organizers demanding she "tone down" her act for Queen Elizabeth II.

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The controversial "Poker Face" hit maker was invited to play the annual event, attended by the British monarch, but was told to refrain from wearing provocative costumes at the Opera House in Blackpool, England.

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The pop star complied and was given a crash course in etiquette, but she still managed to stun the audience by playing a piano lifted onto giant stilts while dangling from a swing and wearing an Elizabethan-style cloak in red leather.

She says, "I have had to tone down my act generally. But all of that doesn't matter because I'm a massive fan of the Queen, I was so excited and have even been practicing my curtsy."

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"When I first came up with what I was doing, I said, 'Oh my f---ing God, I hope she likes it!'"

Lady Gaga closed a show that featured performances from veteran entertainer Bette Midler, classical singer Katherine Jenkins, Miley Cyrus and Mika.