She's a svelte, dark-eyed nymphet, the ultimate teen sex fantasy. He's a blue-eyed boy wonder with a Peter Frampton hairstyle. Together, they discover love in a sun-soaked Eden thousands of miles from the nearest bottle of moisturizer, jeans boutique or parent. In suggestive designer loincloths they grope their untested way through each other's pleasure zones, joyously liberated from the constraints of guilt or convincing dialogue.

Sound familiar? Columbia Pictures thinks so, which is why it filed suit against Embassy Pictures in Los Angeles on May 17, charging that Paradise, starring Phoebe Cates and Willie (Eight Is Enough) Aames, is a "blatant" and "inartful copy" of Columbia's blockbuster, The Blue Lagoon, featuring Brooke Shields and Christopher Atkins. Astonishingly, Paradise co-star Cates agrees. She castigates the film as "a rip-off." Only 18, the sassy, hard-edged Cates is cynical about how movies get made. (Her father and uncle are both filmmakers.) "The backers of Paradise," Phoebe contends, "knew exactly what they wanted: to make money." Columbia was aware of the Paradise project even before it started, she says. "I'm surprised that they didn't try to stop production then."

A lawsuit was inevitable. Seeking an injunction against the film and its advertising, Columbia put its case before Judge David Kenyon, who just six weeks ago ruled that Great White, a $7.5 million shark story from Film Ventures International, had to be withdrawn from movie theaters. The judge declared the plot and characters had been stolen from Universal City Studios' Jaws.

In its case, Columbia had the support of the critics. "Paradise is to ... The Blue Lagoon as apples are to apples," sniped Variety, adding that "rarely in recent memory has a film so completely 'borrowed' the characters, plot and even ad campaign of another." The New York Times tersely dismissed Paradise as a "Blue Lagoon with camels." Indeed, Columbia was able to mount a scene-by-scene comparison of the films to show just how far the similarities go. In addition to the cloned hairstyles and dress, both couples have their sexual consciousnesses raised by books filled with sketches of naked human bodies. Later both girls become frightened when they menstruate for the first time while bathing in a lagoon, and both tease the boys about masturbation. Near the end of the films, both girls become pregnant, Brooke actually giving birth, Phoebe conveniently returning to civilization just before the onset of labor. Columbia concluded, "There are simply too many similarities for it to be coincidental."

Not so, claimed Peter Bierstedt, senior vice-president of Embassy Pictures. Bierstedt argued that the 1908 novel The Blue Lagoon, from which the movie of the same name is adapted, is "public domain in the United States. We could have based our movie totally on it" without fear of copyright violations. Embassy ridiculed Columbia's claim of ownership of "a common and popular subtheme...of young love in an Eden-like setting."

On May 27 Judge Kenyon ruled in Embassy's favor. Admitting there were similarities between Paradise and The Blue Lagoon, the court nonetheless decreed that "the general ideas of the movies at issue are different." The judge cited the chase motif in Paradise (Cates is continuously pursued by the Jackal, a lecherous Arab slave trader), which has no counterpart in Lagoon. So Paradise will continue its rounds of U.S. movie houses. Ditto the ad campaign, which features the scantily clad couple looking like Adam and Eve. Judge Kenyon ruled that "the pose of loving couples, even against a tropical background, is too common to constitute protectible expression."

So far the box office take of Paradise, which cost $3.4 million, has been no match (just $12 million) for the staggering $140 million gross of Blue Lagoon. Perhaps the legal hype will help. Co-star Cates, however, thinks Paradise deserves to languish. The New York model turned actress admits she jumped at the chance to star in her first movie role but says that "I don't consider Paradise to be a professional experience. There was no depth to anything I did in it—and it wasn't entirely my fault." Cates explains she was rushed: "It was sort of like 'Okay, one or two takes, that's good.' " Phoebe adds that she took the part because "when you start out, you have to make compromises, which include doing films of lower quality."

One conciliation Phoebe made for Paradise was agreeing to do nude scenes. "In this business," she says, "if a girl wants a career, she has to be willing to strip." Cates insists she has no objections to "tasteful" nudity. "If you've got a good bod, then why not show it?" But Cates was infuriated by what she viewed as "real exploitation" by Paradise producers, who used a body stand-in for her without her knowledge for a variety of nude close-ups. As a result, Cates refused to do any promotion for the film. "I didn't show up at their parties, didn't go to any screenings, didn't travel anywhere they asked me to."

Further rankling Phoebe are statements by Willie Aames, 21, that he was Cates' acting mentor during the filming of Paradise in Israel. "Pretty amusing," she sniffs. "Willie doesn't like rehearsing, and I don't think he's such a terrific actor."

Born and raised in Manhattan, Phoebe is the daughter (she has two sisters) of TV producer Joseph Cates. Her first goal was dancing, not acting. She studied at the Professional Children's School and the Juilliard School, but at 14 a knee injury sidelined her. She then began a highly successful, if unfulfilling, modeling career, appearing in such magazines as Seventeen and Glamour. "That didn't teach me anything," she says. "It was just the same thing, over and over. After a while I did it solely for the money." A screen test in New York led to the Paradise role. "I asked my father, 'Should I do this?' " she recalls. "He said, 'How can you even question a lead in a feature film?' I said, 'Yeah, but what about the nudity?' And he said, 'What are you going to do, model for the rest of your life? What are you so hung up on nudity for?' That's all I needed. I took the part."

Cates soon realized modeling had not prepared her for the movies. "Modeling teaches you to be completely conscious of the camera. Acting is being totally unconscious of it." Her next role, that of a schoolgirl in the comedy Fast Times at Ridgemont High, due in August, is a step up from Paradise, she believes. Meanwhile she has kicked off a singing career that has already taken her to Italy, where her theme song from Paradise is No. 1 on the charts.

Phoebe shares a spacious riverside apartment in Greenwich Village with boyfriend Stavros Merjos, 23, a booking agent for commercial directors. They met three years ago during her first night at Studio 54 with family friend Andy Warhol. "Phoebe's terrific because she takes everything that's happened to her in stride, without ego or attitude," says Stavros. Part of that, admits Phoebe, stems from insecurity. "There are a lot of actors out there who've made one or two films and who never work again," she notes. But things look promising. "The market is really youth-oriented these days. I'm getting tons of scripts." Yet, as she showed after making Paradise, her dedication to a film career hasn't tempered her criticism of the industry. "People follow proven formulas in any business," she says. "These days I guess you could say that the film business is the worst."