Katy Perry's California Dreams Tour

Kristian Dowling/Picturegroup

In her adopted hometown, the singer delivers infectious enthusiasm with plenty of sugar.

Katy Perry has never been apologetic about her brand of sugary sweet pop. From the cherry Chapstick line in her breakout hit "I Kissed a Girl" to the confectionary avalanche of her "California Gurls" video, which features the singer butt naked in a cloud of cotton candy and shooting cream out of peppermint candy-inspired breasts, the calorie count on a Perry single spikes to the many thousands -- in the best way.

You could say the same of her California Dreams world tour, which hit Perry's adopted hometown on Aug. 5 for the first of three sold-out nights at Los Angeles' Nokia Theatre (she returns to the Staples Center across the street in November). And judging by her audience, of whom at least half looked under the age of 12, the kid-in-a-candy-store theme was entirely appropriate since that's exactly what it felt like to peer upon Perry's pastel stage with its pink cloud-shaped video screens, gigantic lollipops, rainbow-colored stairs and candy cane accents.

It's all part of an elaborate fantasy sequence that she's cooked up, explained (somewhat) by a video that gives nods to The Wizard of Oz and Alice in Wonderland with a hint of The Goonies and airs intermittently throughout the show. And if that's not enough visual stimuli, Perry also provides a troupe of dancers -- eight in total -- and costumes that include a human slot machine (for "Waking Up in Vegas") and a giant purple cat (for a cover of Whitney Houston's "I Wanna Dance With Somebody").

But it's her own wardrobe changes -- more than a dozen during the nearly two-hour show -- that take the, er, cake. From the lime-green casino-ready gown of "Waking Up in Vegas" to the sexy black catwoman suit Perry wears during "Circle the Drain" to the Hershey's Kiss-themed bikini of "California Gurls" and candy button dress of the closer, every piece of fabric is choreographed to tell a story -- but not to distract from the vocals as seems to be the case with so many pop stars whose voices either don't translate live or simply aren't strong enough.

Neither was the case for Perry, who proved her range with a jazzy version of "I Kissed a Girl" and ballads such as "Not Like the Movies" and "Thinking of You," the latter which she performed from a cloud-like podium that trolleys above the crowd. She also silenced any potential naysayers with pitch-perfect delivery of her singles, opener "Teenage Dream," "E.T.," "Hot N Cold" and the show's final number, "Firework." Sure, she's sung these songs a zillion times, but you wouldn't know it from the enthusiasm Perry puts out, the sign of a true pro.

Where she lacked that overachiever confidence is in the dance department, and there are plenty of moves she's had to master, including a stupefying sequence during "Hot N Cold" where Perry changes five outfits in a flash. Then again, she more than compensates with some sexy, racy moves -- not a Nicki Minaj lap dance, per se, but the lyrics to Perry's "Peacock" ("I wanna see your peacock, cock, cock") came with some suggestive microphone handling.

Perry got to spread out with some covers, too, including Rihanna's "Only Girl (In the World)" and Willow Smith's "Whip My Hair." She delivered -- rather impressively -- a snippet of Jay-Z's "Big Pimpin'" during a sort of acoustic time-out in center stage, but it was a surprise appearance minutes later that would prompt several thousand jaws to open in disbelief as Rebecca Black walked out to join Perry in the chorus to "Friday." It was, after all, a Friday, and since Black, an Orange County native, appears in the video to Perry's "Last Friday Night," a duet was only fitting. Talk about a crowd-pleaser; perhaps they should consider touring together.

Not that Perry needs help with ticket sales, as the 7,100-seat capacity venue was filled to the rim with faithfuls -- mostly female, but even in cases where the boyfriend or husband got dragged along, no one seemed unhappy in the end as smiling crowds filled the L.A. Live courtyard.

For some of her time onstage, Perry wore her own version of Dorothy's ruby red slippers, even chanting the famous line, "There's no place like home" halfway through the show. It's a sentiment she shared with the locals during her three-night stand, a sweet one at that.