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Perry with a decorated taxi outside her London listening session for Prism on Sept. 27. The singer recorded the album mostly in her hometown of Santa Barbara, Calif., and Stockholm.
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The singer held a junket with European journalists on Sept. 25 for her new fragrance Killer Queen. One reporter asked her what her childhood smelled like and Perry responded, ''The smell of my childhood? Well, if you've ever smelled a Bible, that's what my childhood would smell like. The pages of a Bible.''
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For her arrival at her Killer Queen launch party at Berlin fragrance store Douglas, Perry rode on the back of a Harley followed by a posse of bikers.
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The Killer Queen launch had around 2,000 screaming fans in attendance. Perry took photos and signed autographs for nearly two hours.
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Among the many fans wanting to catch Perry's eye was a drag queen dressed as the star. She later brought him inside the launch party for a photo op.
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Perry went through most of Prism for the crowd of British journalists, record execs, and bloggers. Before the innuendo-laced jam ''Birthday,'' she tells them, ''I took my mind to a place where Mariah Carey existed in the '90s and that whistle was still pristine.''
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Perry rehearsing in London with her band for ''Part of Me'' for her iTunes Festival performance.
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Perry works out the choreography with her dancers for her new single ''Dark Horse.''
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Her male dancers join Perry for a military-themed version of ''Part of Me.''
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Perry and her dancers take a bow at the Roundhouse theater in London. Later, she'll say that she liked the performance but needs to work on her endurance for the physically draining shows. ''I'm just building endurance to get back into it,'' she says later. ''I was eating fatty foods and just being in love for a good eight months before this. So I need to get back in that mode.''
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Perry and the dancers go through ''Dark Horse'' for dress rehearsal hours.
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The singer doing the dress rehearsal of ''Wide Awake,'' which climaxes with a confetti drop on the audience.
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For more on Katy Perry's wild world, pick up a copy of EW on newsstands today or buy it online now.