Rebound, as Demure as Ever: Shania Twain at Caesars Palace, Las Vegas

LAS VEGAS — This city doesn’t necessarily mean the end, not anymore. It’s a town of summation, site of neither genesis nor graveyard. For a singer a residency here isn’t merely a sinecure for the once-was but a confirmation of cultural saturation. If you can make it here, you’ve made it everywhere.

For Shania Twain, who not a decade ago was one of the biggest pop stars in the country, Las Vegas means a second chance. On Saturday night she was at the Colosseum at Caesars Palace for the opening night of a residency during which she will perform several dozen shows over the next two years.

She took to the stage on a motorcycle suspended in air, wearing a sparkling bodysuit, and for about an hour and a half revisited the over-the-top glitter of her arena tours of the late ’90s and early 2000s, though in a more controlled format. All her old personae were on display. In places she was the rural Canadian girl made good, and in others she was the pop-country diva who rewrote genre rules.

It was normal enough business, apart from one thing: Excluding the dry runs for this show, Ms. Twain has not performed in public since her “Up!” tour ended in 2004.

That’s not to say she hasn’t been in the spotlight. In 2008 her marriage to Mutt Lange, who produced her best albums, collapsed when he left her for one of her close friends, making for tabloid spectacle. She had an appealingly loopy guest judge stint on “American Idol” in 2010. And last year Ms. Twain began a career comeback in modern fashion with a cleansing, often disturbing memoir, “From This Moment On” (Atria) and a self-help-seeking reality show, “Why Not? With Shania Twain,” on theOprah Winfrey Network.

Re-emerging as a very public neurotic was in many ways a brave thing. That TV show was in part about Ms. Twain’s struggles with her voice. Sometime since the peak of her fame, for reasons either physical or psychological, it had abandoned her.

It is back now, even if this busy, rotely dizzying new show didn’t take full advantage of it. Ms. Twain was backed by 10 band members, 3 backup singers — including her sister Carrie-Ann Brown — and 4 dancers. Sometimes, as on “Don’t Be Stupid (You Know I Love You),” they swallowed her whole, and sometimes her backup singers threatened to drown her out altogether.

But when things calmed down, Ms. Twain sounded comfortable and strong, especially during a segment late in the evening when she invited some fans onstage to join her for a campfire singalong. Near the end of the night she rode onto the stage on a white horse and sang her megaballad “You’re Still the One,” looking the horse in the eye, and her voice was milky and resonant. After that came “From This Moment On,” where she outpowered the phalanx of strings behind her.

While arena-size ballads helped cement Ms. Twain’s pop stardom, her most thrilling songs were often her loosest, those in which she unanchored country from its self-seriousness. They were standouts here too, like the comically exhausted “Honey, I’m Home,” “I Ain’t No Quitter” and the exuberant “Man! I Feel Like a Woman!” (Few artists have given the exclamation point the workout that she has.)

Ms. Twain released only four studio albums, and just three were important. Those were the ones produced by Mr. Lange, all of which have been certified diamond, for shipping over 10 million copies: “The Woman in Me” from 1995, “Come on Over” from 1997 (double diamond) and “Up!” from 2002. Whatever mountains Taylor Swift is climbing, Ms. Twain’s flag is already at the summit. By the time of “Up!” she was country by blood but not always by association. That album was released in three versions — pop, country and international.

Ms. Twain also tore up the fashion playbook for a country singer. At one point during this show she wore a multicolored rhinestone tank top with a hooded leopard-print cape and matching palazzo pants. Like all the outfits it was a nod to the clothes of her past: a montage of old videos showed her transition from midriff-baring country girl to proto-Lady Gaga/Nicki Minaj.

A Las Vegas revue is in theory a hypertrophied, theatrical take on an artist’s past, but when you have achieved what Ms. Twain has, and in sometimes gauche but always grand fashion, a show like this can only seem temperate by comparison. The crowd was a blend of Shania die-hards, cowboy princesses, taking-in-a-show curiosity seekers and two-drinks-in celebrators; all of them could have handled more pomp. Ms. Twain used to specialize in extravaganza, and this show was merely flashy and energetic.

While Ms. Twain has been writing new songs — one of them, the banal “Today Is Your Day,” was part of this set and suggested an airless singer like Colbie Caillat far more than it did Ms. Twain — there are no formal plans for a new album, though that’s the certain next step.

A Vegas residency symbolizes stability for aging stars in an increasingly fickle marketplace; this theater also hosts the residencies of Celine Dion and Rod Stewart. But for Ms. Twain, who’s largely been a recluse, there is a strange dissonance to the pageantry required of an endeavor like this, which includes riding into a news conference on a horse and an interview with Robin Leach in the local paper.

There is also the merchandise, much of it crammed into a shop just outside the theater: a black top hat for $20, T-shirts for up to $60, eau de parfum for $35. Most charming were the red shot glasses with boot-shaped grips for $10. They read “Whose Bed Have Your Boots Been Under?” That was Ms. Twain’s first hit with Mr. Lange as collaborator, and during this show it was one of the high points, perhaps because what was once a cheeky jab now has heavy resonance. Just before she sang it she talked about how thrilling it was to be “kicking up some dust.” And then she opened her mouth and let those old wounds heal.