Malibu Beach is a place where celebrities go to feel ordinary and ordinary people go to feel special.

To the movie stars who put it on the map it is a retreat, an endless vista of ocean and a tiny town where they can do the things ordinary people do - grocery shopping, jogging and hanging out at the deli - without being noticed.

To the tourists and star-struck locals who trek here in summer and on weekends it's a magical place, a stretch of mostly unspoiled beaches and a small community where, by chance, they might just brush elbows with a screen idol or two.

And to the rest of the people who lived here Malibu is a seaside home - happily shared with gulls, seals and pelicans - that is increasingly threatened by developers and by state efforts to share it with more people.

It is also the place where my mother grew up and where I, as well spent much of my childhood. And although Malibu has changed drastically from the small row of cottages and the lone drugstore of my mother's day, many of the denizens' joys, lifestyles, attitudes and concerns are the same today.

"Tacky Chic." That's how one of today's Malibu hostesses describes the lifestyles of her family and many of her neighbors. She lives in the fabled movie colony, an enclave of some 100 eclectic beach-front houses just north of a surfing beach. Her neighbors include such diverse talents as Sir Laurence Olivier rock musician Robbie Robertson, Jascha Heifetz, Merle Oberon, Rod Steiger, John Housman, Dyan Cannon, Neil Diamond, Willy Wyler and Linda Ronstadt.

"Part of it," the hostess says, surveying the row of fancy and plain beach-front patios from their own exquisite one, "is that every house is something else. Yours may be next to a shack."

At current prices, such a shack could fetch a fortune. Malibu beachhouse prices have inflated along with home costs elsewhere in the country. And the state's recently voted coastline environmental control came at a time when Californians were becoming increasingly aware of a scarcity of beach-front property.

An average house in the movie colony, says real estate broker Vicki Pierson, now goes for around $500,000 to $600,000. And that buys just four bedrooms, a living room, kitchen, a couple of bathrooms and a sea-front teahouse, on a 30-foot-by-200-foot lot with septic tank.

"There aren't too many fixer-uppers left," says Pierson, who lives in the colony.

Indeed. Many once modest cottages have blossomed into seaside palaces, taking on the identities of their most famous occupants in the process. On the site of the old "Lana Turner House," for example, stands "The Mary Tyler Moore House," a grand affaire with carefully manicured beachside gardens.

But renovation can take a human toll. "This beach has the highest divorce rate per square inch of any area of the country," claims one resident. "The Grant Tinkers (Mary Tyler Moore and her husband) built a palazzo. Mary is a fastidious woman and . . . (building) that house damn near broke their marriage." It's tough to build with no sewer system and with sea-air corrosion, the neighbor explains. "They moved back to town and are getting along fine."

The house, since sold to film executive Richard Block, is still called "The Mary Tyler Moore House."

A star's cachet also sticks to rented houses. "People call for a rental and say, 'I'd like the Streisand house or the house Robert Redford rented,'" says Pierson. "Redford has rented several and I have to find out which one."

The Malibu of today is a 27-mile stretch of beaches west of Los Angeles. The Riviera-style beaches, snuggled close to the Santa Monica Mountains, are alternately broad and shallow, and often backed up by steep bluffs and dunes. The land was bought by banker Frederick Hastings Rindge before the turn of the century, and remained a private ranch for his widow May, until a state highway, law suit and taxes led to the sale of parts of it.

Malibu's identification with movie stars began when the Rindge family first started leasing lots on the beach. When my grandparents built a cottage there, in the late 1920s, theirs was the fourth house in the movie colony, a tiny enclave on the edge of the rancho.

Among their neighbors was actress Louise Fazenda and her husband Hal Wallace, Barbara Stanwyck, singer-actor John Bowles, and songwriter Nacio Herb Brown ("Singing in the Rain"). With a drugstore soda fountain the only store in the area, lie was casual, even ordinary. Except that when my aunt, trapped in the surf, was rescued, her rescuer was John Wayne. And on the beach my grandfather once encountered a young women who asked him where he was going. "To look for a pretty girl," he said. "Let me get my hat and go with you," she said. It was Jean Harlow.

My mother's first house burned in one of Mailbu's many fires. The family rebuilt, this time installing electricity.

My own childhood at Malibu unfolded in the early '60s, five miles north of the movie colony, at Malibu cove, a small beach with a long view of Point Dume. Point Dume with its pale yellow cliffs, surfing beaches and hidden-away houses is doubtless familiar to regular watchers of "Harry O" or "The Rockford Files." It has long been a favorite film setting, and moviemakers have tried to pass it off as Dover as well as the beach of "Beach Blanket Bingo." Recently it was used to film "The Last Tycoon."

Our home and the ones around it were built on pilings, and a high tide waves would crash against them, shaking the houses.There, on weekends, vacation and in summer, we would escape suburbia, freeways and daily routines to fish, sail and sunbathe, and watch the sun sink over Point Dume, illuminating the sky in pinks, oranges and reds that were reflected in the kelp beds and surf.

Our street, though not guarded, was private. The houses - mostly simple, boxy and functional with glass walls looking out over the ocean - were homes to a teacher, an editor, an airline pilot. We also knew a sprinkling of celebrity neighbors (Leon Uris and TV actor Vic Morrow).

But Malibu Cove is today changed, just as the movie colony no longer has many modest "shacks" among its mansions.

With beach-front property prices so inflated, the new owners tend to be richer. This means they can afford to erect grander homes, fit for year-round living, and live out their fantasies in designing them.

Styles range from Tudor to ultramodern. Linda Ronstadt lives in a cozy clapboard while actor Bruce Dern's home boasts a seaside English garden.

The newer houses at Malibu Cove are two-story affairs - many with stained-glass windows and beveled glass doors either custom-made or salvaged from old buildings.

The new neighbors include Dick Clark of American Bandstand fame, whose two-story modern home has a tree growing in it. Director Robert Altman inhabits an enormous glass home and is adding on a swimming pool and projection room. There is also an eastern princess, a rent-a-car executive, an architect and a lawyer.

Up the beach even more opulent palaces are springing up atop the bluffs overlooking Paradise Cove. Yvette Mimieux lives in one just a brief walk from the $3-million Spanish-style villa built by financier Max Palevsky. Above Point Dume, Bob Dylan has constructed an enormous onion-domed estate.

But the most imposing Malibu home now under construction is going uo on a hill overlooking the movie colony. It's owner, a local doctor, is trying to duplicate an old English castle.

People in Malibu, like homeowners everywhere, like to complain about their home-maintenance problems. The elements make upkeep difficult. Salts air corrodes. There are no sewers, and septic tanks must be periodically pumped out. A major storm can carve away valuable sand and cause bulkheads to sag or break.

One movie clolony family, a neighbor recalls, was hit by a tide so high that "they got the grunion running in their living room."

And there's always the threat of fire. Malibu's mountains are perennially overdry, and fires regularly sweep through the area. Pepperdine University, recently built on the mountainside, is "a $38-million fire break," a colony woman quipped.

But neverthless Malibu continues to lure the rich from their luxurious Bel Air havens. "Some people treat it (Malibu) as if they're in Portugal," says one resident who moved to the colony after flirting with the idea for a while. What hooked her family, she says, looking at the limpid ocean, "was the infinity."

Malibu, dotted with fast-food joints, doesn't have what its tonier residents consider a good restaurant, so the celebrities generally don't hang out in the handful of eating spots along the Pacific Coast Highway. "We keep to our homes," says a wealthy woman who is a long-time movie colony resident. "A lot of emelettes are consumed here."

One popular eating spot is Bagelah, a pine-paneled delicatessen opened by Chi Chi hairstylist Bernie Safire under his Malibu salon. The deli features pastrami and various sandwiches named after Rod Steiger and other famous patrons.

But all is not perfect in paradise. Crime is far from a major problem in the movie colony, with its private street guarded by a gatekeeper. But there is a wee bit of pilferage going on that has some residents a little unnerved. "It's petty thievery," says one resident. "The children have free access to the houses." Tape decks are taken. Outdoor pilloww vanish. In one case, the resident recounts, a freezer in a garage was broken into and stored meat taken. A lock was put on the freezer. It was broken and meat again stolen. Two locks were put on, and the freezer itself was stolen. "None of the parents want to report these thefts," the woman says. "The sheriff just holds his head in his hands."

"Keeps Out" the signs warn at the entrances to Malibu's private road. And that's what many of the beach residents would like to tell outsiders who come to picnic, camp or hang out on their beaches.

It's a message that was repeated in the early part of the century by May Rindge in her efforts to keep the state off her rancho. In those days armed guards patroled the Rindge land on horseback, shooing out trespassers, and in at least one case shooting at them. My mother recalls the time she was a child and was trespassing at Malibu Lagoon, then Rindge property. A guard pin-pointed his gun from across the Lagoon and fired a warning shot. Other times she and her sister would sneak through barbed wire fences to explore the vast Rindge estate and wind up being sent away by the guards.

Today there are no guards on horseback, but private patrols do keep trespassers from doing much more than walking on wet sand. And today's outsiders are not residents of neighboring beaches, but hordes of daytrippers, called "Valleys," who flee the parched inland communities of the San Fernanando Valley.

If you go down to Paradise Cove and Point Dume, a young Malibu Cove neighbor explains, you can see how the locals "chase the Valleys" out. People can tell who comes from where. The cool little Malibu types" are invariably tan, thin and athletic, says the neighbor, who happens to fit that description. The Valleys do not, and those who venture to sit on beaches below privately-owned homes "are made to feel unwelcome." The Valleys who park their cars on streets near those risk having their autos damaged. And Valleys who surf are expected to stay at the public surfacing beach just south of the movie colony. Those who came up on to Point Dume (Malibu territory) may even be threatened with knives, the neignbor says. So the Valleys wind up on a public beach near Paradise Cove Pier or, if they're willing to walk several coves away, at Pirates Cove. That beach, relatively remote, also is a favorite spot for nude swimmers.

The Malibu residents' desire to keep outsiders out is reflected in recurring battles over whether the are should have sewers. "It's the most divisive issue" in a community of McGovern liberals, says one resident, a liberal who favors sewers as opposed to "living on top of diphtheria."

Opponents say sewer lines would bring in more apartment developers and ultimately more people.

People here point to the public beaches and trailler parks scattered along the coast and some tell stories of havoc wrought by trespassing outsiders.

"We used to hire a professional to set off firecrackers right on the beach on the Fourth of July," recalls a movie colony resident. "Then every junkie and hippie started to drift in. Kids got into the punch and got drunk." The custom was stopped for four or five years until last year some residents arranged a Bicentennial celebration. "It started in a burst of democratic spirit," she notes wrly. A rock band was hired to play on the beach and a food buffet with wine and beer was set up. "The word went out and people were running around and passing out cold." Those people were outsiders who walked in from the public beaches. "It became the year of the all-time holocaust," she says.

"We're enviromentally concerned here," says real estate brother Pierson, walking on the sand past the movie colony, on a sparkling day. Then she adds: "It's incorrect to say all things should be done for the poor. Why don't they feel people who are affluent have some rights? It would be a shame to let them alter this."