We used to call them Saturday Night Dances.

Boys in cashmere V-necks would line up to one side of the dance floor; smoking cigarettes, smelling of English Leather and watching the door for crashers.

Girls would hide in the ladies room, putting on too much eye makeup and chewing Juicy Fruit. The Beach Boys would sing, "Do you wanna dance?" And we danced.

Now they're called discos and we're called singles. The Appletree, Washington's hipstready-chic hangout, is what really happened to the Class of '65. Themen hover by the dance floor, smell of Musk oil, and V-neck is now The Patch of Hairy Chest. The women retreat to the ladies room, which is covered in silver mylar Jean Harlow wallpaper.

The dancing dolls have swayed from flat to fluffy.

And the crasher, in 1977 is none other than Rocky.

"Yeah, Sylvestor Stallone showed up one night in a sweatshirt," recalls doorman Dennis Shillen. "I told him he wasn't appropriately dressed. So he and his bodyguard, who was wearing a leather jacket, changed clothes and came back later in jackets." The comeback kid came back in the late rounds one more time.

Shillen is watching the Appletree's back door, where celebrities, VIPs and regulars make their entrance. The management issues VIP cards (more than 1,200 or card-carryers so far) which allow the holders to skirt the line for the special entrance at the back door. So the back door is really the front door and the front door is often the back door.

"It gets silly sometimes," says Shillen, "but these people like to feel exclusive. That's why they come."

A couple appears at the door. Shillen doesn't recognize them. "Aw, come on man, its' raining," they plead. Shillen breaks down and lets th couple pass.

Why?

"Compassion," the doorman replies.

Boogie fever . . .I got the boogie fever . . ."

The disc jockey in the glassed in booth spins them out, one by one. The dances stand then out and strut them out Bump, Hustle, Bus Stop, The Rope. No prize winners here. Even the clite got their toes stepped on. It's hot and smokey; by 11 o'clock the Ban-Lon shirts are getting sticky. Elbows jabbing, knees knocking - it feels like a basement recroom. Between discs your partner asks the same questions he/she did back then; the somewhat sensitive "What's your name?," the alwasys provocative "Where did/do you go to school? and the hard-hitting "Do you come here often?"

You get the BEST of my love . . .

"I come here on weekends," says Michael, a 24-year-old firefighter from Vienna, Va. "To dance . . .and whatever fringe benefits." He pauses, feeling shy "But some place you ask a girl to dance and you'd swear you just asked her to go to bed"

He shakes his Afro and heads for the bar - where the boys are. They stand in three, dressed in the finest cruisewear, staring blankly throughly the smoke. "This is nothing but a BX," says Roger, a pudgy executive. "A body exchange."

A young woman standing nearby licks the pineapple in her Pina Col, ada, brown eyes darting from mustache to mustache.Denny, 23, says she alwasy comes to The Appletree with a girl friend - never alone - and never with a date. "Why? Look around! Of course, they all have lines," she says, "but you can usually tell if someone's a nurd."

You don't have to be a star, baby . . .to be in my show . . .

The APpletree is known for its celebrities. Sly, Sonny, Clint, Liz, Tom, Englebert . . .but tonight its mostly Omar Sharif lookalikes playing backgammon. Persians, Arabs and Iranians roll the dice, move the chips around the board and wink at the women who stand and watch.

"I don't like those foreigners," says Cindy Raabe, a 21-year-old aspiring actress from Potomac. "They treat their women like trash. I'd rather have respect than money."

Cindy is a "regular" at the Appletree and tonight in her red chiffon off-the-shoulder gown, she is part Lolita, part Mae West. "I get dressed up to come here. One night I wore my silver lame pants, but they wouldn't let me in," she drawls. "They go for more of a "natural" look here, rather than the "disco" look. Disco and money don't go together."

Not the way disco and sex do. A waitress remembers the night Englebert Humperdinck came in. "Or was it Tom Jones? Any, he wanted to know where the 19-year-old girls were." Another time, a Persian man asked for 20 girls "just like her" for his friends. She blushes. "I told him we don't provide women."

"Don't leave me this way . . .I can't survive/and stay alive/without your love . . .Oh baby, don't leave me this way . . .

Eligible bachelors like David Kennerly and Barry Goldwater Jr., were irequent patrons of the APpletree at its peak last summer, when the lines were so long there was talk of forgoing passes. "Washington's a fickle town," says one waitress. "In six months it will be someplace else."

Like Tramps, where owner Mike O'Harro'schutzpah draws the big names the limos, the designer clothes. Like Tiffany's and the Pierce St. Annex. Even the life in the fast lane needs a change of scenery.

But tonight, it's "Joy to the World" in dosco, touchy-feely on the tiny dance floor, congested cloak rooms and only a forty-minute wait in the rain.

"The dance floor's too small. The deejay's bad, the drinks are watery, it's too hot and too crowded," complains Davis Vroden from Chicago. He's been here once before. Why did he come back?

"I like all these things."