BEVERLY HILLS, Calif. — "R U the Girl with T-Boz & Chilli" is sort of a revolting concept that is, nonetheless, somehow charming.

But only because of its stars. Not because of the show.

T-Boz and Chilli are the two surviving members of TLC, which, we're told, is the most successful girl group in history. And in "R U the Girl," which debuts tonight at 7 p.m. on UPN/Ch. 24, they're looking for someone to sing with them in place of Lisa "Left Eye" Lopes, who died in a car accident in 2002.

But . . . they're not replacing her . . . they're just putting someone in her place . . . for a while . . . for the show.

"To us, it was very important that the show did not come across as if we were going to replace Lisa," Chilli said.

But . . . that's exactly the way the show comes off. It's the way UPN is selling it to viewers.

T-Boz and Chilli wade through thousands of audition tapes and pick a group of finalists. They pop in on those women unannounced; they bring this group together; they narrow the field; they get it down to two finalists; they pick a winner.

But . . .

"Actually, TLC is T-Boz, Left Eye and Chilli, so we're not replacing Left Eye," T-Boz said. "I just want to say that off the top. But (the winner will) be joining us to perform in the concert and on the song with us."

"Of course, this girl's not even going to come close to replacing or comparing to Lisa, but that's not what this is about," said executive producer Jay Blumenfield.

But . . . the goal of the show is to find that girl to sing with them.

"We want her to be a triple threat — to be able to sing, dance, rap. Great personality," Chilli said. "Sense of humor is very, very important to us because we're extremely silly. And she has to be special in our eyes. So we'll know it when we see it."

But . . . this is apparently just a one-time thing. T-Boz and Chilli will continue to perform as TLC (without the L), but they won't be adding a new member on a permanent basis. Apparently.

"This is actually something Lisa would have supported, as well, because she's into giving back to the fans, and this is giving a special person an opportunity to fulfill their dreams," T-Boz said.

Ah, yes, it's all about the fans. It's not about T-Boz and Chilli trying to get back into the limelight.

Well . . . actually, it is about that. Which they freely admit.

"If you guys haven't figured it out, we are the black Laverne and Shirley," Chilli said. "It's so crazy because it just seems like things gel between us.

"And going on this journey, going into the girls' houses and their jobs and making these ambushes was so fun."