In the opening scene, Mad Max guns the engine of his flaming yellow Chevy Camaro with the front and rear spoilers and thick slicks on the back. He and his black-leather-clad partner roar of on a collision course with the black-bearded, earringed baddie, who is doing 120 down the desert strip in a hopped-up Chevy Nova with a supercharger on the hood.

"I'll blow the sucker away!" says Max's partner, pointing a double-barreled shotgun out the car window at the baddie's head. But the bad guy just roars a pirate laugh, his moll giggling beside him. He swerves and, incredibly, reverses direction, screaming tires laying enough rubber to blacken the hot, flat strip. He gets away -- for 89 more minutes.

"They look just like the couple in the car behind us," said Georgenne Timko to her date, Paul Jones, as they sat in a meek Volkswagen beetle at Oxon Hill's ABC Drive-In last weekend.

In fact, there was one "muscle car" on the 30-year-old lot -- a souped-up, gray-primered Chevy Nova whose passengers did resemble the movie baddie and his moll. But it was not the drive-in scene of 17 years ago, when gas was cheap, hearts throbbed at films like "Love With the Proper Stranger," and Oxon Hill youths drag-raced the quarter mile on I-295 in the wee hours after the show.

Yet just as in the late 1950s, when the outdoor movie was at its peak as a national cultural phenomenon, a show at the drive-in remains an inexpensive family night out, offering patrons as much fun off the screen as on.

Virtually no new drive-ins have been built in the United States since 1958, when their number peaked at about 4,000. Only 3,102 drive-ins remained as of last June, but of the 13 still operating in the metropolitan area and the 33 in Maryland, nine are alive and well in Prince George's County. There, low- and middle-income families can still get an inexpensive breath of fresh air over a six pack or two, munch snacks from home or buy them from the snack bar, and hoot and holler at the good parts of the show without embarrassment.

And the "Hot-Rod Hearts" can still spark in the dark, though some hearts are not as young as they used to be.

"Whoooeeeeeeee!" howls Bob Thomas at the monogrammed sides of designer jeans well filled by a apir of blonds. The women turn around for a second, to check out the $1,500 black lacquer paint job on Pat Friason's 1968 Plymouth Belvedere-GTX (409 cubic inches of displacement at the ready), in which Thomas sat.

"That's the mating call of the native Oxon Hillian," said Thomas, insisting that it is definitely possible to cruise a drive-in from the back seat of a friend's car.

In their days at Oxon Hill High School, Thomas, now 32, and Friason, 28, spent many Saturday nights meeting their friends at the ABC and other drive-ins. Those were the days when the drive-in was the cheapest place around to take a hot date.

"You got to see two movies and popcorn was cheap," said Bob Wilneland, 25, manager of the ABC theater and scion of the family that owns four of the nine drive-ins in the county. "A coke and the lady was happy for the evening; that's what it was to us."

Friason's wife Cathie sat in the front passenger seat. She was one of the girls who came to the drive-ins in groups during high school. Even without the adolescent intrigue, they still think the drive-in is the only way to see a movie.

"You're outside, you can smoke in the comfort of your own car, and you don't have to deal with sticky floors either," Cathie said.

"It was a lot easier to tell your parents you were going to the drive-in than hanging out on a parking lot," she continued. "And you don't .have to worry about cops chasing you off like they do at McDonalds."

"A walk-in theater's like a funeral home," said Thomas, whose T-shirt declared his allegiance to "kickass rock and roll." You can't be yourself, you have to follow traditional etiquette. You can't make out with a chich, raise a lot of hell and meet people," he said, taking a beer from his styrofoam cooler, then setting it into a plastic holder hooked over the door.

Is there really sex in drive-ins?

"Sure, it's real. If anybody denies it, they're lying," said Thomas.

"Heck yeah, that's the best part," chimed in Pat Friason. "The windows get steamed up and everything."

Up in the front row Tim Schauer, 34, and Oxon Hill High class of 1965, fondly remembered the steamed-window days ("When I was much younger, in my courting age"). Now a "bachelor father" of two teenaged girls, Schauer finds the drive-in a good way to entertain and keep an eye on his daughters at the same time. They lay on a shag rug on the roof of the car, watching one of Mad Max's futuristic police cars crash through a mobile home.

The crowd signs, "Oh, s---!"

"This was the scene for the popular Oxon Hill 'debutantes,'" upper class high school girls with guys who lettered in sports. "They had to be seen in the most acceptable company," Schauer recalled.

"They're all in their thirties now, but there's always a new crop to carry on the tradition," he said. His daughter Vivian, 14, is a freshman at Oxon Hill High and Jackie, 13, is a ninth grader at John Hanson Junior High, which their father also attended. Asked how they would meet boys on the roof of the car, Jackie replied, "I've already got a boyfriend, but I wouldn't know about her (Vivian)."

The drive-ins became an American passion when the men who fathered the baby boom generation came home from World War II.

"Families had new autos, gas rationing was lifted and we all had this love affair with the automobile," said Paul Roth, owner of the Ranch Drive-In in Clinton and the 301 Drive-In in Waldorf. In those days, "all films were made for all people." Roth has been in the family film exhibition business for 33 years.

After the war it was cheaper to build a drive-in on the edge of what would become suburban sprawl than one of the elaborate downtown movie palaces, particularly because steel was still in short supply. Going to the downtown movie was a dressy affair, Roth said, but the drive-ins caught on because people could be casual, even bohemian, in the privacy of their cars.

It was then that drive-ins developed the features that make them popular to this day: a cartoon for the kiddies, who got in free, two features for the adults and a snack bar with a wide variety of food and drink. Today it is virtually impossible to see two recently released movies for one admission price in an indoor theater, and admission is generally $1 to $1.50 higher than at a drive-in.

But the average drive-in required four to seven acres of land that was increasingly valuable, particularly if the property were commercially zoned. Prince George's owes its wealth of drive-in theaters to the relatively low price of its land.

Roth and ABC manager Wineland said their business has picked up in the last year. The ABC needs about 150 cars to break even on a slow night, but Wineland said his lot has been filled with 875 cars several weekends this summer. A good week brings in a gross of $24,000, or approximately 480 cars a night, he said.

Most area drive-ins operate only from March through November. Because they must wait as late as 9 p.m. for darkness, they cannot draw two separate audiences for the main feature. It is profitable, therefore, to have a second feature to hold an audience late, and to have an amply stocked concession stand to serve them.

Besides, the lower price and the double feature are part of the drive-in tradition.

"Suppose you walk into a deli restaurant," Roth explained, "You expect to get bread and pickles on your table -- it comes with the place. That's what the public is used to and that is what they expect. You don't want to be the first guy who's not going to do it," he said.

In these inflationary times, on a muggy Saturday night, the drive-in was the best excuse for Diane and Donald Huff to leave their crowded Alexandria home in the family double-cab pickup, with 3-year-old Kristina and 12-year-old Troy in tow. They have been steady drive-in goers since they were married 12 years ago.

"If they have a good show it's really worth coming," said Diane, reclining barefoot on a patio lounge in the truck's rusted bed, facing the screen through the open tailgate. "It costs $3.50; if you look at $2 an hour for a babysitter, it really pays." Her husband, wearing a "Six Pack Attack" T-shirt, sat on a faded green folding chair next to a styrofoam cooler filled with diet soda, beer and a fifth of Chivas Regal. He sipped the Chivas and soda from a Wendy's paper cup. They arrived an hour before dark and the cartoon, to give the children some time in the playground next to the screen.

"It gets them aired out and (hopefully) ready to conk out," said Diane.

"If it weren't for the drive-in, we'd probably be sitting home fighting tonight," said Donald.

"I just hope they never get rid of drive-ins," said Diane. "It would be like taking a piece of America."