Vegas Stage Reviews: 'Siegfried & Roy'; 'EFX'; 'The History of Sex'

Speaking of hair, remember when David Cassidy's cascaded past his shoulders and you thought Shirley Jones was the coolest mom in the whole world for allowing such a thing? Well, the hair is cut short, Cassidy is 48, and he's Vegas' resident former superstar — here to remind us (and this information will cost you at least $45 a ticket) that he's still kicking, not to mention singing, leaping, and flying through the air in the monolithic, cast-of-thousands $45 million musical-variety show EFX (MGM Grand; 800-929-1111). Cassidy stars energetically as a busboy who takes a journey through his childhood imagination, bounding into the shoes of Houdini (magic tricks!), P.T. Barnum (trapeze artists!), and H.G. Wells (a 3-D time-travel movie! You can keep the glasses!). To call EFX a star vehicle is an understatement. It's a star battleship; you may never see a live show this extravagant, which makes it somewhat important and a joy for the kids. But the show's script makes The Partridge Family look like the Brontë sisters, and that makes EFX weirdly pornographic — so much to see, so little to think about, and after you've seen enough of it, your own boredom might surprise you. Until Cassidy starts pattering with the audience, shaking us awake with self-deprecating humor and a few topical jokes. The audience roars, free for the moment of empty glitz and common-denominator humor. Under Cassidy's famous hair lies EFX's brain.

Then again, who goes to Vegas for brains? I, for one, was titillated by the town's promise of south-of-the-neck entertainment. But while the signs on some shows say ''adults only,'' they're largely PG-rated affairs, many of them operating on the premise that audiences are still capable of lip-smacking over two bare breasts, even when their showgirl owner is otherwise covered in gowns by Bob Mackie wannabes and Teletubby headdresses. The T&A arena seems wide open for shows that can appeal to audiences born after 1955, and there is a new show that does just that: The History of Sex (Golden Nugget, 702-386-8100). Starring handsome Broadway vet Michael Gruber (Cats) and gorgeous Candace Davis (she paid her dues singing on Norwegian Cruise Lines, bless her heart), The History of Sex bounces through the titular topic, beginning with a nearly naked Adam and Eve and consistently — cleverly — objectifying with equal opportunity the 12 Fosse-esque whistle-worthy male and female dancers. In a retrofitted version of the Cole Porter ditty ''Let's Do It, Let's Fall in Love,'' Gruber tells us that ''For cash a girl on the phone does it/George Michael all alone does it.'' That's smart stuff by Vegas standards, making the small-scale, unassuming History of Sex the best adult bet in town at $29.95 a ticket. This is not to say that Siegfried & Roy and David Cassidy should take their clothes off, but even Gloria Stuart might appreciate a good George Michael joke. Siegfried & Roy: B- EFX: B The History of Sex: B+