Katy Perry Wows On California Dreams Tour (PHOTOS)

Katy Perry kicked off the London leg of her California Dreams tour Thursday night in a skimpy ballet inspired outfit, among several costume changes.

Katy recently told Rolling Stone about going on a diet to prepare for the 95-date tour.

"I'm on a meal plan, which absolutely sucks," she said, "but on Sundays I get to have a cheat day where I go buck wild and eat In-N-Out Burger. Then I'll work out, go to a vocal lesson, run through the entire set at rehearsals, go to dance rehearsal until 10:00 p.m. and then go home and sort through e-mails concerning the production. I feel like I'm training for the Olympics!"

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