The Fab Four is a Beatles tribute with impersonators saluting three eras of the band. From left, Frank Mendonca as Paul, Gavin Pring as George, Tony Felicitta as Ringo and Steven Craig as John.

The tribute band Fab Four never imagined it would be competing with the real Beatles organization when it started playing Las Vegas more than five years ago.

But then, the guys doing the show now couldn't have imagined, because they're not the same guys.

The Fab Four is a lean little enterprise compared to Cirque du Soleil's new Beatles-sanctioned "Love." But it's successful enough that the group has cloned itself for the past year and a half at the V Theatre in the Desert Passage mall. "Fab Four Mania" is the group's own cheeky little reference to "Beatlemania" -- not the real Fab Four but an incredible simulation, to paraphrase the "Beatlemania" tagline.

"Even a seven-week run at the (Las Vegas) Hilton was pretty trying on our families," explains Ron McNeil, the original Fab Four's John Lennon, who oversees both operations from Orange County, Calif. The twin band is "keeping our name in Las Vegas, and keeping some of the competition out."

"Mania" includes McNeil's brother, Frank Mendonca, as Paul McCartney. The new "pre-fab four" perform almost an identical show to the one people saw at the Hilton from 2002 through 2004. It starts with the same recorded announcement from Penn Jillette that everything is played live, covers the same set list and the same funny film clips to cover costume changes. And it too has an Ed Sullivan impersonator (Paul Terry) to surprise the audience as announcer and comic relief.

It was gratifying, McNeil says, to see the response and realize people "weren't only coming to see us (the original lineup), but the show we worked on for 10 years."

The show adheres to what has become a typical Beatles-tribute formula, dividing into three segments to offer the 1964 mop tops (alas, seriously inflexible helmet-head wigs are another shared trait with the original lineup), a "Sgt. Pepper" set in the album cover's military uniforms and a "Let It Be" finale with the band that's all but broken up.

What sets this show apart are the musical details and the tone. The group takes its mission seriously when it comes to playing "A Day In The Life," but knows when to back off and make anachronistic jokes: "I bought (my costume) at Wal-Mart." Breaking character helps them steer clear of an overly theatrical approach that just wouldn't work with the club setting and a small stage, where the elevated drum riser already jiggles precariously.

A cast of four will always offer a little bit of give and take. Mendonca doesn't sing ballads such as "Yesterday" quite as well as the original band's Ardy Sarraf. Tony Felicitta doesn't sound one bit like Ringo but has a winningly likeable stage presence. Steven Craig as Lennon and Gavin Pring as George Harrison -- a genuine Brit from Liverpool -- are both astonishingly close in look and sound.

And the live musicianship on authentic period instruments conjures up that primal rock 'n' roll energy that's entirely missing from the $100 million "Love." It turns out that only about a half dozen songs are entirely duplicated between the two shows (not counting the dozens that "Love" samples in fragments).

While "Love" quite appropriately emphasizes the wide range of sound George Martin conjured in the studio with the Beatles, a little show like this reminds you that it all started with four guys playing in a band together -- and having fun doing it before it all got too complicated.