Some dance stories are a lot more than dance stories, and this is one of them. The Khmer Classical Dancers, who appeared yesterday afternoon in an outdoor performance at the Neptune Plaza fronting the Library of Congress, are exquisite artists to watch and listen to, the legatees of a thousand-year-old tradition. But the sheer fact of their appearing, at this time and place, is a human miracle, the latest amazing chapter in a saga of dispersion and tragedy, danger and subterfuge, perseverance and survival.

The Khmer troupe represents the living remnant and budding posterity of what used to be known as the Royal Classical Khmer Ballet, which flourished under the old Cambodian monarchy and visited the United States for the first time in 1971. When the Khmer Rouge made its savage sweep of the country in 1975, the dancers and musicians scattered into exile, many becoming farmers and feigning illiteracy to escape revolutionary retribution. After years of subsistence, a number found their way to refugee camps in Thailand and began to pick up the threads of their former artistic life. Only last year, means were found to bring them to these shores -- some 35 have now settled in Wheaton, Md., where they are struggling to keep their heritage alive, through teaching, practice and performance.

The dance and the dancers are bewitching in their beauty, refinement and universality. The roots of Khmer dance go back to ancient temple ceremonies, much influenced by Hindu arts and liturgy from the era when Cambodia was under the subjugation of Siam. We Westerners are apt to think of dance as mostly a matter of steps. Like many Eastern arts, Khmer dance is much more holistic -- the feet are only a single element in a complex of movement involving the entire body, from head and features to neck, shoulders, arms, hands, fingers and torso. The dancers' motions, like the accompanying music, are gentle, softly resilient and delicately ornamented; there ae occasional somersaults and handsprings, especially from the monkey figures, but virtuosic flash is not a part of it -- the goals ae expression of character, plot and feeling.

At Neptune Plaza, where several hundred spectators thronged to see them, some dozen members of the Khmer troupe performed four dances, of which the most elaborate was a narrative from the Hindu "Ramayana" epic. The story has echoes of the "Odyssey" and other Western classics: The god Rama, his beautiful wife, Sita, and his brother are exiled in a forest and set upon by a demon giant who lusts after Sita. The demon abducts Sita, is defeated in battle by Rama and his monkey army, and the reunited, triumphant couple starts ona long trek homeward. Much of the tale is related in the entrancing sign language of the Indian mudras (symbolic hand gestures), but scenes like the abduction and the battle, though stylized, are recognizably realistic.

The cruel turn of world events that deprived these patrician artists of their homeland is now providing our own culture with an incomparable enrichment. In November, the troupe will perform at New York's Museum of Natural History. Here's hoping we'll have the chance to see much more of them in our area.