'Glee' cast on stage: Very 'Idol Live' or very 'Brady Bunch'?

The cast of “Glee” in concert Tuesday night in Rosemont. (Scott Stewart/Sun-Times)Working on “Glee,” the hit Fox TV show about unnaturally talented show choir teens, must be absolutely exhausting. The show airs weekly, and each one is packed with not only the usual rigors of a TV production but sometimes up to half a dozen full-strength, choreographed music numbers.

It’s like making an entire album every couple of weeks — the show has already produced three soundtrack CDs, with a fourth on deck — and staging the concert to go with it.

And now they’ve staged a concert to go with it.

The young stars of “Glee” are being trotted across the country for nearly a dozen shows in four cities — one in Phoenix, four concerts last week in Los Angeles, two this week in Chicago and five this weekend in New York. Tuesday night’s show at the Rosemont Theatre pried the popular songs out of the show’s slavish story lines and lobbed them onto the stage as a bright, colorful, costume-changing musical revue. It’s very “Brady Bunch Variety Hour.”

But it’s also refreshing to see the music and the young stars’ vocalizing — often so electronically tweaked on TV it makes your teeth hurt — out in the open.

Like the “American Idol” tours, this is a chance for fans to see whether the kids can actually sing. They can. And how. Opening with the song that cemented their first hit, the kids of New Directions bah-bah-bah’d their way into “Don’t Stop Believin’.” From there it was a high-impact, high-energy 70-minute show featuring most of the highlights from this first season. Rachel strutted through the crowd belting “Don’t Rain on My Parade.” Puck grabbed a guitar and led a sing-along of “Sweet Caroline.” Mercedes climbed atop an actual black SUV to sing “Bust Your Windows” (no actual windows were busted). The vocal adrenaline ran high, and when the voices were discernible above the piercing squeal of the crowd, the talent was impressive.

If you wonder why I’m referring to the performers by their character names, it’s because that’s who’s on stage. Glee Live is not a showcase for Broadway’s Lea Michele. This is uber-ambitious Rachel on stage. The kids are in character the whole time. Even Kevin McHale (as Artie) remains in the wheelchair (a cruel taunt just a week or two after “Safety Dance”).

The show is adult-free, too, though Will (Matthew Morrison) and Sue (Chicago’s Jane Lynch) appear in pre-taped segments. Coach Sylvester even gets in a Crisco joke about Will’s hair.

It’s a relentlessly jubilant affair, and watching the cast leap and dance and hit extraordinarily high notes — the upper register of Kurt (Chris Colfer) is positively scary — one can’t help get the sense that, aside from the commercial jackpot, this show was assembled partly for this cast to feel the adulation, to face their celebrity, to just take a victory lap.

All this hoopla, and the first season of the series hasn’t even ended yet. That happens June 8, and it’s already been renewed for a second and third season.