For most "American Idol" fans, [article id="1609245"]Adam Lambert[/article] is the wildest, most unusual contestant they've ever seen on the show. But to his friends and castmates in Los Angeles' long-running variety extravaganza "The Zodiac Show," the Adam you see on the "Idol" stage every week is nothing compared to what they've witnessed back home.

Lee Cherry, "Zodiac" co-creator and director, first met Lambert in Europe in 2003, when the singer was touring with the musical "Hair," and he directed Lambert in his "Zodiac" stage debut in 2004. "He did [Sam Cooke's] 'A Change Is Gonna Come' and as Randy would say, he blew it out the box, dog," Cherry said. "That was pretty much the first time in L.A. anyone saw him being Adam in all his full fabulousness, and everybody lost their minds."

Several years later, at the most recent "Zodiac" show in December, Cherry said Lambert wrote some songs with Madonna collaborator Monte Pittman, and he got a real sense of how far the 28-year-old singer could go. "That was a big collaboration and a big production number, where he had the whole outfit and the dancers and the whole thing. ... We love seeing Adam do his thing how he loves to do it, and you've only seen the half of it on 'American Idol,' " Cherry said.

The six-year-old "Zodiac Show" started as an underground, after-hours monthly party hosted by Los Angeles' dance and glam-rock communities that grew into an irregular series of big, one-off productions at the city's Avalon Theatre. The events revolve around a sign of the Zodiac, and they include every kind of performer imaginable, from singers, dancers and actors to comedians, jugglers, fire-eaters and high-wire acts. It's been described as a "rock 'n' roll Cirque du Soleil."

Part of the reason Cherry thinks Lambert is doing so well on "Idol" is because of the experience he's had onstage at the "Zodiac," performing his own outrageous glam-rock songs, as well as [article id="1608851"]creative covers of other songs[/article] and learning how to be part of an ensemble. "Before 'American Idol,' [he] didn't really have an outlet for his talent, to do it the way he wanted to do it," Cherry said. "Every time he was working, he had to fit into some kind of box. He was doing it because he had to do it, he had to live. But on our stage is where he got to ... bring the black nail polish, bring as much glitter as you can bring, what's the craziest outfit you can. It's never too much, except for when it is. Because sometimes, sometimes we ... "

Scarlett, the show's other co-creator and co-lead singer, interrupted Cherry: "We have to tone him down," she laughed.

Like, for instance, the time he wanted to perform a song with a flaming headdress, and they had to convince him it was too dangerous.

Cherry, Scarlett and co-creative director and former Pussycat Dolls member Carmit Bachar said they are all immensely proud of Lambert's success on "Idol," but they're not surprised he's doing so well on such a mainstream national stage.

"I think that it's really been beautiful on the show to see him grow and take in all the comments and the constructive criticism and really add it to his performances, and he's so humble and so beautiful, and he means it and he's real," Scarlett said.

That doesn't mean they weren't a bit worried that America wouldn't know what to do with a eyeliner-wearing, banshee-wailing, glam-rock, emo theater kid who didn't exactly fit the more traditional style of an [article id="1609151"]"Idol" front runner[/article]. "He's really cut out for this on every level," Cherry said. "[But] we ... honestly didn't know how he was going to be received. We thought he was either going to get kicked off right away or he was going to win. We figured it was going to be one or the other. We knew he was going to be the best singer of the bunch by far."

After conferring with Lambert early on, Cherry posted a number of the singer's "Zodiac" performances on YouTube, including the very David Bowie-esque glam-rock original "Crawl Thru Fire" from last September, which has garnered more than 400,000 views to date. While each "Zodiac" revue is full of performances from a variety of Hollywood artists at the top of their respective games (choreography, dancing, songwriting, makeup, singing), he said Lambert has that indescribable "it" factor that sets him apart even on a stage with other super-talented performers.

Scarlett said despite Lambert's unusual background and flamboyant (for "Idol") style, she's not surprised America is embracing him. "They heard somebody breaking through," she said of the early embrace of Lambert. "When you're witnessing something like that, it's undeniable, even if you're from, like, Arkansas. You're like, 'Oh, my god, I'm watching a star. This is incredible!' "

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