BRINGING IT ‘BACK HOME’ TO OLD L.A.

The lights go up, and we’re on Sunset Boulevard with the bygone billboard sitters. Then it’s off to the Olive-Lanai apartments, Canter’s Deli, the Pomona Freeway, MacArthur Park, the Hard Rock Cafe, Venice beach. The travelogue in song is brought to you courtesy of “Back Home . . . a Los Angeles Musical” (at the Cast until June 1), an affectionate paean to Our Town.

“We wanted a show L.A. could take pride in--and that could take pride in L.A.,” explained director Robert Schrock, 40 (and, with Kirby Tepper, the book’s co-author). “People write shows about New York,” said Indiana-born Schrock. “Why not L.A.? The city is growing up, becoming sophisticated, adventurous.”

But . . . not perfect .

“Where you are always has some bad things in it,” agreed California native Tepper, who wrote the music and lyrics and performs in the production. “The whole time I was in New York, I had people picking on L.A. Now, I know what’s wrong with L.A., but it’s still a wonderful place. So the Valley girl (a character in the show) is fine, the lawyer’s fine. They’re all fine.”

Well, perhaps not all . Tepper, 28, acknowledged that the character of ballet teacher Miss Twitter (from “A Bun in My Hair”) was inspired by the uppity “bunheads” he danced with in “On Your Toes.” As for actors Rob Lowe, Emilio Estevez and Judd Nelson (immortalized in “The Brat Pack Fight Song”)--”We don’t really think they’re that bad,” said Schrock.

“I do,” said Tepper. “I’m a nice guy, but I love to pick on those people.”

Yet they both stress that the satire is rooted in a gentler impulse: feelings about one’s hometown. (The story line follows Midwestern Pat from her wide-eyed arrival in “L.A.,” through a series of amusing, painful and often strange encounters.)

“The title doesn’t really refer to any one place,” said Schrock. “The show is centered in L.A., but the heart of it is what it’s like to be somewhere that’s not home. And that’s a universal feeling.”

Added Tepper (whose local stage credits include “Casual Sex” and “The Glitter Palace”): “We’ve had people from Chicago, New Jersey, Kansas City--and they all identify with it. Maybe they don’t know about Spago’s or the Hard Rock or Gorky’s. It doesn’t matter.”

Another non-alienating factor is the show’s lack of emphasis on the entertainment-industry life style.

“Of course, you can’t do anything about L.A. and not mention entertainment,” said Schrock. (Hence the “Off-Off L.A.” tribute to local theater.) “But this is not a story about someone coming here to get into show business. We didn’t want that, we’d seen it too many times. And we’d lived it.”

Though the show was originally conceived as a revue (Tepper had written half a dozen songs and had begun working with cast member Earlene Davis before he met Schrock), the two men quickly set about filling out the material.

“We got together and said, ‘OK, we need another guy, a soprano, a blond-guy type,’ ” Tepper recalled. “So among actors we knew, we had a few auditions, got people who would sing the material with us, whom we could write for. And we ended up writing the characters around them.”

“Having been a writer/actor/director,” Schrock said (he claims 636 performances in New York as the mute in “The Fantasticks”), “I visualized how to direct it while we were writing it. So it all developed together.”

Noted Tepper, “One thing Bob kept us to as we were going along was parameters: knowing the concepts of set (minimalist), props (five stools, three jackets, four scarfs and two hats, interchanged among the cast) and context. Once those outlines are clearly drawn, you know what you have to do and to say.”

As for the emotional aspects of their collaboration, “It’s like a marriage,” Schrock conceded. “We don’t always agree, but we respect each other enough to listen.”

And the final product?

“I love sitting back and watching the show--and I can’t separate what I did, what Kirby did.”

Added Tepper:: “We know who directed, who wrote the music. But the rest of it--the ideas, scenes, the feelings--that’s us. “