At 19, she is one of the highest-paid models in the world: Her daily rate is $2,000, and her income exceeds $200,000 a year. She has already adorned dozens of magazine covers and scores of ads for everything from Cutex nail polish to Calvin Klein jeans. With a good decade of modeling ahead of her, she stands to be one of the fashion industry's all-time moneyspinners. But for Esmé Marshall, that is not enough. Last month she left the man and the agency with whom she began her modeling career two years ago—Johnny Casablancas and his Elite Model agency. Now she is the sole client of a new agency backed by Casablancas' bitter rivals, Jerry and Eileen Ford of the Ford model agency. For Esmé the decision to switch was strictly business. "Elite was getting too big," she says. But along Madison and Seventh Avenues her defection has been widely read as the escalation of a long and bitter power struggle in the $50 million-a-year modeling industry. Casablancas, for one, is now steeling himself for all-out war. "Eileen Ford's game is crystal-clear," he says. "She wants my skin. There's so much ego and conniving in this business—anyone will do anything. But I am a warrior. I will fight. I will never sleep with both eyes closed as long as that woman is around."

The Fords disdain such rhetorical splutter. "I haven't got time for it," says Eileen coolly. "Shakespeare had a phrase for all this—'Much ado about nothing.' " But the Fords are still nurturing a deep grudge—and a $32.5 million suit—against Casablancas, who was their Paris associate until 1977. Suddenly that year he moved to the U.S. and founded Elite by pirating some of the Fords' highest-priced talent (PEOPLE, June 13, 1977). Ford is still the world's dominant agency—three times as big as its nearest competitors, Elite and Wilhelmina Models Inc. But with the death of Wilhelmina's charismatic founder and namesake last year and the volatility inspired by the war between Ford and Elite, all bets are off: Defection has become epidemic. Last month alone, $300,000-a-year model Patti Hansen left Wilhelmina for Elite, and Beverly Johnson, the highest-paid black model in the industry, bounced from Elite to Ford and back again in the span of one week. "Our rates have doubled and things couldn't be better," says Beverly happily. "We used to undercut each other for plum assignments, but now the models are good friends. It's the agencies that are at war."

Models are, of course, in the middle of the war. Agencies make their money collecting 10 to 20 percent commissions on all assignments—and their weapons in the battle over the hot, Midas-like faces range from flattery to treachery. Boyfriends are reportedly bought off by some agencies for their secret support, promises are made to models that cannot finally be kept, and their egos are pampered shamelessly. In the current atmosphere a sense of betrayal turns swiftly to thoughts of litigation: Star models Christie Brinkley and Anna Andersen, for example, are both suing Casablancas in the wake of their defections from Elite. Conversely, a model's sense that she is wanted for more than her good looks creates the strongest bond of all—and seems to be a primary reason for the rash of recent desertions. Explaining her decision to leave Wilhelmina, Patti Hansen says vaguely, "It's like, my family doesn't think I've changed, and the agency didn't see that I had changed." More concretely, she implies the Wilhelmina staff would not adapt to her work in movies. Thus Casablancas wooed Patti away, stroking her ambition.

Top fashion photographer Francesco Scavullo sees all the competition as a shell game. "It is silly," he says. "A great model is a great model—changing agents is not going to turn a 26-year-old into a budding 15-year-old." Casablancas agrees in a way. "Models know agents will go to any lengths to get them," he says frankly. "It's a little bit shameful. Sometimes I don't really like this business."

The allure of Fame Ltd., the new agency run by Jerry Masucci, 41, and one-third owned by the Fords, is precisely its promise of personalized, aggressive promotion. Masucci, a former music producer who claims his salsa label, Fania, has had some 100 gold records in the last 16 years, insists his motive is profit, not revenge against Casablancas: "I'm doing what I do best—making money and stars." Jerry—a former New York policeman who went to law school at night, once did public relations for Fidel Castro and now drives around town in a blue-and-silver Rolls—is seen by industry insiders as a mere soldier in the war between Ford and Elite. Masucci says he can handle whatever comes. "I've been through it all," he says, "like smuggling sound systems into Panama. If you can throw a concert in South America and get out with money, this is kid stuff."

For the 19-year-old Esmé, however, it is grown-up stuff indeed. The daughter of a onetime Chanel model, she was spotted by a Mademoiselle editor while working in a clothing store in Cambridge, Mass., during a year off between high school and college. Now she's put off college for herself, though she's helping to put sister Phoebe through Sarah Lawrence. Her own thoughts run to such notions as "starting my own corporation to handle business and earnings and to have a couple of products on the line. The most important thing for me now is to trademark my name before anybody else does." Some say Esmé is already overexposed, but she disagrees: "I don't believe it's possible. You just shouldn't do too many sleazy ads. When people love to see you, they love to see you everywhere."

Casablancas says he worries that Esmé is "under a negative influence—her boyfriend [boutique owner Alan Finkelstein] is destroying her career, and he's deep into a drug indictment." In fact, charges against Finkelstein stemming from a 1976 marijuana bust have been dropped, and Esmé dismisses the reports that Finkelstein has a cocaine habit and that she does as well. "That's ridiculous," she says. "A lot of people like to blow things out of proportion." She sees her defection to Fame as a great leap forward. "When I met Jerry Masucci and told him my ideas, it was just too good to be true," she recalls. "He agreed that models should be represented as talent instead of just faces." Then she pauses reflectively, wise as well to the perils of the model wars. "I've seen 13-year-old girls at jobs recently, and to me that's even more reason why there has to be a lot more attention paid to the girl. These kids—and I guess I'm still a kid—can be messed up for life."