Travolta, then 24, was on the verge of becoming a global sex symbol by the time he suited up in black as Danny Zuko, the rebel in Grease without a mean bone in his body. He was beloved as the snake-hipped heartthrob Vinnie Barbarino on ABC's Welcome Back, Kotter, and had just finished shooting the megahit Saturday Night Fever. "John was peaking," says Dinah Manoff, cast as Marty of the sassy girls' clique the Pink Ladies. "His sexuality was coming out in his voice, his legs and his acting. We were mesmerized." A song-and-dance man at heart (he had toured in the stage production of Grease), Travolta was thrilled just to be in a musical. "I enjoyed every minute," says Travolta, 44, wed since '91 to actress Kelly Preston and the father of Jett, 6. "It's classic. It's timeless."

Oddly, his career slipped after Grease, and it would be more than a decade before 1994's Pulp Fiction reestablished him as a major star, albeit a chunkier one, leading to his current presidential gig in Primary Colors. "John was so young the first time," says his sister Ellen Travolta, 58, who had a bit part in Grease as a waitress. "Now it's going to keep getting better and better."

Olivia Newton-John

"Grease was the single biggest event of my life," says Newton-John, 49, who played Travolta's girlfriend, Sandy, a wholesome Sandra Dee clone. "It affected everything." (And still does: Her daughter, Chloë, 12, likes to go to sleep with the tape playing on the VCR.) Newton-John, whose duet with Travolta, "You're the One That I Want," became a No. 1 hit, recalls her weeks with the cast as "a wonderful summer. It was like going to a school that I'd never gone to." This decade has been a hard-knocks education for Newton-John, who grew up in Melbourne. Her sportswear line, Koala Blue, failed in 1991; she was diagnosed with breast cancer in '92; then she and her husband, actor Matt Lattanzi, split in '95. Things have picked up lately. She rerecorded her 1974 hit "I Honestly Love You" with Kenneth "Babyface" Edmonds and, more important, has a clean bill of health. "You can go down the tube or you can fight," she says. "I realized I could fight."

Stockard Channing

She may have scored a Tony (for 1985's A Day in the Death of Joe Egg) and an Oscar nomination (for 1993's Six Degrees of Separation), but Channing, it seems, will be remembered for generations to come for Grease. "I was at an audition recently," recalls Channing, 54, "and these little girls came rushing in -- and they were like 5 -- and yelled, `Where's Rizzo?' Not even their mothers were 5 when we did the movie!" At 34, Manhattanite Channing was the oldest of the "teens" when she played the 18-year-old tart-with-a-heart who has a pregnancy scare when Kenickie's "25-cent insurance policy" fails in the back of his car. So has she ever considered revisiting Rydell High onstage? "Are you mad?" shrieks the quadruple divorcée currently costarring in the movie Twilight. "I've been otherwise engaged with my life."

Jeff Conaway

Conaway was no stranger to Grease when he won the role of Kenickie, the tough-talking T-Bird. But a two-year turn as Danny Zuko on Broadway in the early '70s did little to prepare the Queens, N.Y., native for Hollywood. "You're thrown into the jaws of success, and it's a heavy thing," says the actor, now 47 and a devout Christian. "I fell right into the trap." After Grease, Conaway played cabbie Bobby Wheeler in Taxi for three seasons but ditched it all in 1981 to pursue a movie career. By then he was addicted to cocaine, and his personal life hit the skids. In 1985, his tumultuous five-year marriage to Olivia Newton-John's older sister Rona, whom he'd met at a Grease cast party, ended in divorce. He survived on small TV roles before finally kicking his addiction in 1991 and has since been diagnosed with clinical depression. Four years ago, Conaway, who lives in Hollywood with current wife Kerri, a magazine editor, parlayed a three-line part on the syndicated series Babylon 5 into a steady role as security chief Zack Allan. After all his troubles, he says, "I'm just happy to be here."

Didi Conn

"At the time I was like a madwoman," says Didi Conn, 46, explaining the oddball electricity she brought to the part of Frenchy, a Pink Lady and a beauty school dropout. "I was charged up, happy to be in Hollywood." The Brooklyn native now lives outside New York City with her second husband, Broadway and film composer David Shire (Norma Rae), and son Daniel, 5. She may be playing mom these days, but she still has a squeal of a voice. "This guy was so sexy," squeaks Conn, recalling the dream scene in which Frankie Avalon serenades her. "I'm drooling thinking about it."

Though known now as Stacy from PBS's Shining Time Station, Conn sees Grease as a personal high watermark and has published a memoir, Frenchy's Grease Scrapbook, to coincide with the rerelease. "I hired two secretaries, went to Radio Shack and got a tape recorder," she says. "I got to reconnect with everybody. It was like no time had gone by."

Frankie Avalon

Avalon was weary of being typecast as a '50s pop icon when producer Allan Carr offered him the role of Teen Angel. "My gut reaction was, 'I'm not interested,' " he recalls. In the end, superstition swayed him: The scene in which an angel croons "Beauty School Dropout" to a bevy of teenage girls dressed in white mirrored a recurring dream that Avalon's cousin had told him about years before. But though the movie exposed the former Beach Party star to a new generation of fans, it only reinforced his retro image. These days the crooner, 57, who lives in the L.A. area with wife of 35 years Kay, is a staple on the Vegas circuit and occasionally appears in films, including 1995's Casino, in which he was typecast again -- as himself.

DINAH MANOFF

At 19 -- and in her first movie role, as Marty, the sex-kitten of the Pink Ladies -- Manoff projected more spunk than she possessed. "I thought I was ugly, I was fat, I wasn't good," she recalls. "I spent my time giggling and putting my head down. I was overwhelmed." Still, it wasn't long before the daughter of actress Lee Grant and TV writer Arnold Manoff found her own footing in showbiz, with roles in TV's Soap, the 1980 movie Ordinary People and a seven-year stint on Empty Nest. Hoping soon to direct her own screenplay (husband Arthur Mortell will produce), the mother of 1-year-old Dashiell is a shrinking violet no more. Now when she watches Grease, Manoff says, "I think I'm so adorable."

Lorenzo Lamas

After presidential son and aspiring movie actor Steven Ford decided he was too nervous to play the role of Olivia Newton-John's jock boyfriend (even though the part had no dialogue), Lamas, a strapping 6'1" and 220 lbs., was more than happy to step in. After all, says Lamas, 40, the son of actress Arlene Dahl and the late actor Fernando Lamas, "I was going to have some scenes with Olivia -- the goddess!" He didn't even object when producer Allan Carr decided he looked too much like a T-Bird and told him to lighten his dark hair. "I would have dyed it green, fuchsia, anything," says Lamas. Since Grease, Lamas has continued playing brawny hunks on such TV shows as Falcon Crest, Renegade and -- scheduled for fall -- the syndicated Air America. "My career started from Grease," says Lamas, father of a 5-month-old daughter, Alexandra Lyn, with his fourth wife, Playboy model Shauna Sand (he has three other children). "If it's on cable and I catch a bit, I sit down and watch the whole thing."