Stephen Sorrentino does double-duty in "Legends," adding personality as host of the tribute show before suiting up as Elton John. Photo by K.M. Cannon. "American Idol" contestant Jasmine Trias found old-school variety and strong mentoring with the Society of Seven for her Las Vegas debut. Photo by Craig L. Moran.

Funny how two of the least hip shows on the Strip don't seem quite so out of touch if you factor in "American Idol."

It's oft-noted that "Idol" is a phenomenon in spite of -- or maybe because of -- the fact that it's old-fashioned at heart. Young contestants tackle pop standards they may be too young to really remember.

"Idol" only lacks that final step of putting them in costume. If you're going to cover songs by Celine Dion or Stevie Wonder, why not dress up like them?

Maybe if the ratings slip.

For now, you've got "Legends in Concert" or the Society of Seven, which is really stirring up the pop culture blender. Lani Misalucha, the usual featured diva, is on tour. So the old-school Hawaiian variety act recruited a fellow islander, Jasmine Trias, to take her place through March 18.

Trias was an "American Idol" contestant with Jennifer Hudson, who just won an Oscar for "Dreamgirls." Trias steps up (in her own persona) to belt out Hudson's big song, "And I Am Telling You I'm Not Going." But she also puts on a partial costume to imitate Beyonce, who stars with Hudson in "Dreamgirls," as well as Diana Ross, whom Beyonce's "Dreamgirls" character is famously based on.

The afternoon show at the Flamingo also requires Trias to sing a little Janet Jackson, whom you also can see imitated by Karin Lawson in "Legends." The Imperial Palace's 23-year-old tribute show was getting a bit moldy, so it freshened things up by adding versatile Stephen Sorrentino, who appears both as himself and Elton John.

Consider all lines blurred.

"Legends" is tricky to appraise on a long-term basis, because the cast rotates and the quality varies. For this lineup, any momentum Sorrentino contributes to the early going is wiped out by the first two impersonators.

As Rod Stewart, John Anthony's nasal bark bungles the simple job of sounding raspy and parched, something most Las Vegas singers would love to get away with. And go figure why a brief set easily filled with Stewart's signature hits would include not just one, but two songs first made famous by other acts: "Have You Ever Seen the Rain" and "Fooled Around and Fell in Love."

Lawson resembles a muscular version of Jackson, but her segment doesn't go anywhere beyond an aerobic workout with the "Legends" dance troupe.

Sorrentino provides good balance with his personality-driven, pop culture stew: Ethyl Merman covering Led Zeppelin, or a surprisingly serious Groucho Marx crooning "I Remember You." His quick-hit impressions are up-to-date enough to include a Miss USA joke and to delete the Anna Nicole Smith ones.

But it has been long enough since Sorrentino suited up as Elton that he could stand to brush up. He's way too nasal on the choruses, and a double-time "Your Song" robs the song of its quiet beauty.

The homestretch is saved by the bedrock stability of Matt Lewis as a winking Elvis by way of Nicolas Cage, and by Stacey Whitton's obligatory embarrass-the-old-guy-from-the-audience number as Marilyn Monroe. Sorrentino is only guaranteed through May 19, but the idea of having a host is such a good one that Whitton (who also has played Shania Twain) easily could step up if he moves on.

Trias couldn't have picked a better vehicle, or better people to work with for her Las Vegas debut. Veteran Society members Tony Ruivivar and Bert Sagum protect her like a daughter, and she slides into the '70s-TV style of variety as if she has done it for years.

Like most "Idol" finalists, Trias' all-purpose voice emphasizes range over character. But that's no bad thing if you're covering everything from Broadway standards to Britney Spears. (Sorrentino stays current, but this show misses the obvious gag of Britney in a bald cap.)

Besides, her personality is irresistible and the effortless power of her 20-year-old voice is thrilling. If ever another show could be so well-suited -- or if Misalucha decides to tour more often -- Trias has a welcome future on the Strip.