Throw a bit of California into a mixing bowl with Alice in Wonderland, add a splash of Vegas and the result is a show to satisfy the sweetest tooth.
"Awrite?" Katy Perry greets the audience, trying her husband, Russell Brand's, estuary slang out for size. "Let's eat some sweets until we get sick, huh?"
The stage looks delicious, like something fallen straight out of Oz crashing into Willy Wonka's factory on the way down. I'm trying to work out how they're getting the air in the Apollo to smell like cherry ChapStick when gingerbread men burst on to the stage and I wonder if I've fallen down the rabbit hole.
Bubbles, feathers, glitter, cupcakes; it was all designed to distract an audience who might have heard rumours of Perry's weak live performances, but such suspicions went straight out of the window as she opened with "Teenage Dream". Perry's vocals stand tall, no sugar-coating necessary on her powerful voice, the routine nothing short of superb.
With super-slick costume changes in "Hot N Cold", to the simply beautiful "Not Like the Movies", her distinct voice is a never-ending naughty treat, especially on a great set of acoustic covers including Rihanna and Lady Gaga.
She then takes time to interact with her screaming fans. The California girl is great with the London audience, probably something to do with her new obsession with all things English – and she pays a special tribute to her husband's home of Essex.
Even stray boyfriends hanging around the bar could be found bopping along by the time "Firework" and "California Gurls" were played. There's something very more-ish about the American pop princess; I leave the Apollo with an urge to find the nearest bakery. A slice of Perry pie, if I may.