If it weren't for community theater, Jim Jacobs might still be a small-time advertising copywriter in Chicago. And "Grease," the musical he co-wrote with his friend Warren Casey, might never have seen the light of day.

As it is, Jacobs is a well-off retiree who spends his days at his sunny property on the California coast, just north of San Diego. His big break came in 1971, when a little show he wrote for fun with Casey, then an unemployed aspiring disc jockey, opened in a cavernous community theater space on the north side of Chicago.

"Grease" opens at 7:30 p.m. Tuesday and runs through next Sunday

at Shea's Performing Arts Center.

Tickets are $27.50 to $62.50.

For more information, call 847-0850 or visit www.sheas.org.

"I stumbled accidentally into community theater," Jacobs said in a recent interview with The News from his home in California. "I was working as an office boy at the Chicago Tribune, and I met a guy in the research library who was involved with community theater and was always trying to get me to come down and see a show. And I didn't know what the hell community theater was."

Skeptical though he was, Jacobs caught the acting bug immediately, first performing bit parts and working his way up to bigger roles. By and by, he met Casey — a recent transplant from upstate New York — and the two struck up a Laurel and Hardy-esque friendship that would last until Casey's death in 1988. The idea for "Grease," the wildly popular musical based on Jacobs' experiences in high school, which begins a six-day run at Shea's Performing Arts Center on Tuesday, came about as unpretentiously as you can imagine.

"We're sitting around in my apartment in like '69, and it was some cast party of a show," Jacobs said. "Around 1 in the morning, there were still a few old potheads laying around, passed out on the floor. I was sick and tired of listening to Led Zeppelin or whatever the hell I had on the record player, and I dug out some of my old 45s. That's the humble beginnings of it. I was playing Dion and the Belmonts, Little Richard and the Five Satins, and I said to Warren, 'Man, wouldn't that be a gas to do a Broadway show using this kind of music instead of that traditional 'Brigadoon,' 'Oklahoma' stuff that we all know?'"

Casey agreed that it would. And so "Grease" was born, the product of the liquor-fueled whim — "one of those pipe dreams you have when you're half in the bag at a party," as Jacobs put it — of a part-time community theater actor and his unemployed buddy.

The original show — far darker and more dialogue-heavy than the version we know from the impossibly popular 1978 film starring John Travolta and Olivia Newton John and the countless tours and high school productions that followed — opened in February 1971 in a production by Chicago's Kingston Mines Theatre.

The show immediately developed a cult following in Chicago and attracted nationwide attention. One short year later, the show opened on Broadway, launching an international enterprise that has yet to slow down.

The current tour is based on a 2007 Broadway revival of the show, which drew attention — and plenty of critical pans — for casting its lead actors through a little-watched reality show. Though those particular reality stars have long since left the the show for continued fame (in the case of Laura Osnes) or relative obscurity (in the case of Max Crumm), the producers of the tour are betting on public interest in a cameo performance by Taylor Hicks, the winner of the 2006 season of "American Idol." Hicks will play Teen Idol, the angelic figure who descends from heaven to deliver the show-stopping song "Beauty School Dropout."

Those who have wondered whatever became of Hicks since the gray-haired crooner exhausted his brief window of post-"Idol" fame will be relieved to know that he has been happily toiling away in his role as Teen Angel, which he landed in 2008 shortly before the show departed Broadway. Hicks, who spoke to The News from a tour stop in Pittsburgh, said he initially was nervous to perform on Broadway but has since eased into the role.

"I was probably more nervous doing a Broadway show than I was performing on 'American Idol,' just because I'd never done musical theater or acting before. It was a big step for me, but yet I believe it was the right step," Hicks said, in the thick Southern drawl that endeared him to the legions of "Idol" fans who came to be known as the "Soul Patrol." "You do definitely have to be disciplined and committed, but if you love your role and you love what you do, then it's not really work."

"It's not so much of a serious acting role," Hicks continued. "I think that the part of Teen Angel was originally written for a kind of a cameo celebrity role that is out of its element, but yet is a singer and a musician. It's a perfect role for someone like me."

Jacobs, who calls Hicks' performance "very hammy," agrees. But it's hard not to identify a note of wistfulness in his voice as he praises the current production, a nostalgia for the show he wrote with his friend more than 40 years ago. For Jacobs, and for many a critic, the show has lost a piece of its authenticity with each subsequent revival, as tastes turn more conservative and production values get slicker.

"It's getting away from what it was, but the times, unfortunately, have really changed to such an uptight conservative nature over the last 40 years that it's actually astounding to think that when 'Grease' opened in 1972 on Broadway, the reviews said something like, 'What a sweet innocent Valentine to the bygone days of the '50s,'" Jacobs said. "Now, it's thought of as, 'Oh, we can't do it at our school. They show teenagers smoking and drinking beer.' You think, 'What the hell has happened, man?' Each production gets more sanitized and cleaner."

As the sole surviving creator of "Grease," Jacobs finds himself tasked with protecting the show's reputation, an undertaking that grows more difficult with the passage of time. He says he turns down 90 percent of the many requests he receives to use or modify material from "Grease."

"There's tons of stuff, from sleazy people who want to change lyrics and use a song for some shack-up motel on the Jersey Turnpike to rap artists who want to do their versions. You hear them and you go, oh man, this is awful."

For five years, despite an onslaught of requests from television networks on both sides of the Atlantic, Jacobs balked at the idea of turning the vaunted "Grease" franchise into a reality show. He just couldn't bring himself to do it, he said. But when the requests wouldn't stop, Jacobs did what conscientious creative people sometimes do against their better judgment. He consulted a lawyer.

"I said, 'How do you get these people off my back? He said, 'Make outrageous demands. Say you want control of every single facet of it and tell them you want $100,000 an hour.' So I did. And they said OK. They made me an offer I couldn't refuse."

A "Grease" roll call over the years

Barry Bostwick: Danny Zuko, Broadway, 1972

Richard Gere: Danny Zuko, London, 1973

Patrick Swayze: Danny Zuko, Broadway, 1978

Tracey Ullman: Frenchy, London, 1979

John Travolta: Doody, Broadway, 1972; film version, 1978

Debbie Gibson: Sandy, London, 1993

Loraine O'Donnell (local actor and radio personality): Rizzo, 1982, Morrisville College

Rosie O'Donnell: Rizzo, Broadway, 1994

Brooke Shields: Rizzo, National tour, 1994; Broadway, 1994

Megan Mullaly: Marty, Broadway, 1994

Sally Struthers: Miss Lynch, National tour, 1994

Lucy Lawless: Rizzo, National tour, 1997

Taylor Hicks: Teen Angel: Broadway, 2008; current Broadway tour