Ishi was the last wild Indian of North America. He survived massacres, pursuit, hunger, loneliness and a generation of hiding only to die of tuberculosis in a white man's museum.

Dalton Trumbo was the most gifted of the odd group of blacklisted writers known as the Hollywood Ten, of whom four remain alive. He died in 1976 of lung cancer, two years after Hollywood finally awarded him the Oscar he had won under a pseudonym (as Robert Rich, screenwriter of "The Brave One") more than 20 years earlier.

Now, on the gree, rain-Washed foothills of northern California near the slaughterhouse where Ishi surrenidered to farmers and their dogs on Aug. 29, 1911, in full expectation that he soon would be killed by them, film producer Edward Lewis is making a three-hour television movie about Ishi.

The movie is likely to enchance the already formidable reputation of Trumbo, who wrote the first two-thirds of the script, and which was completed by his son, Christopher, after his father's death.

Ishi himself is beyond any enchancement or destruction of reputation. He stands alone as the embodiment of the Yahi, a tribelet of the small Yana Indian nation which was wiped out by whites who came to California for the gold rush.

In 1850 an estimated 3,000 Yana occupied 2,000 square miles of land in the foothills around volcanic Mt. Lassen, which the Indians worshipped as Waganupa. The Yahi were subjected to murder, rape and enslavement, and the main Indian sources of food were reduced by the pollution of salmon-carrying streams with mining tailings and the chopping down of the acorn oaks, from which the Yana made their staple of acorn mush.

Unlike many other California Indian tribes, the Yana resisted fiercely, but with bows and arrows, not guns. By 1872, when Ishi was 3 or 4 years old, there were only two score or so Yana left alive, including a dozen Yahi who had retreated into the mountain fastnesses of their territory.

"Ishi" is the story of the last of the Yahi, and executives at NBC are already whispering that the film, tentatively scheduled for presentation in the fall, will be the biggest special since "Roots." It could be big, all right, but it is as different from "Roots" as Antietam is from Auschwitz, and not the least because there are no Yahi around to cheer Ishi's samll victories.

The long concealment of the Yahi remnant, which suggests the jungle survival of Japanese soldiers who refused to surrender or acknowledge defeat, is known about because Ishi perhaps the only two anthropologists equiped to understand his uniqueness and to ferret out the secrets of his language and his tribe. One of the anthropologists married Theodora Kroeber, a writer who made Ishi's name a household word in western college courses with the publication, in 1961, of "Ishi in Two Worlds," and, later, of a children's book, "Ishi, the Last of His Tribe."

It is the gentler, far more romantic children's book that was purchased for television. The story of this book, and of the screenplay, tells of the tribe's long concealment and of Ishi's caring for its last members. The last four Yahi are scattered in 1908 by a surveyor's party, which raids their cave and takes all of their food, tools, weapons and storage baskets as souvenirs. Two of the four Indians, an uncle of Ishi's and a woman who was either his sister or his cousin, disappear and are never seen again.

Ishi stays with his mother, who is crippled by arthritis. When she dies, he buries her in their ancestral cave and runs into Oroville, nearly 60 miles away. In the final third of the story he is a resident at the University of California museum then in San Francisco, a living relic among relies.

Both book and film are dominated by the dignity good humor, common sense and unflinching courage of Ishi, (The name means "man" in Yahi; from the time of his surrender to his death, Ishi never revealed his private Yahi name.)

Producer Lewis found it impossible to make "Ishi" as a feature film.

"It just didn't have the elements that are fashionable," Lewis says. "To do this without native Americans playing the roles would be impossible, and ther is no starring role for anybody except Ishi. So we couldn't get a star, and it didn't have tremendous violence or melodrama. It's kind of a quiet, gentle story, and I couldn't get it financed as a feature."

Hollywood may have had other reasons, too. Ishi is neither "savage" nor "caveman" nor "noble redman" but a unique and sensitive human being who forges lasting ties of affection with the anthropoligists who befriend him. No easy, tidy morals here.

On the one hand, says Christopher Trumbo, Ishi is the story of what white people have done to Indians in their own country, "about where we've come from, what we are, and what we've done." But it is not just a horror story. "I think Ishi has something to say about the ways people of different races and different backgrounds and different cosmologies can actually be together," Trumbo says. "Call it coexistence, if you want. It's not impossible. It's very real."

Dalton Trumbo's marked copy of "Ishi, the Last of His Tribe" is convered with a plain brown dust jacket, apparently because he didn't want the producers of "Papillon" to know he was working on "Ishi" at the same time. After Trumbo died, Lewis succeeded in getting NBC to buy the script and expand it to three hours. The original screenplay had dealt only with Ishi in the wilds, ending with his capture and confrontation in the slaughterhouse.

When it came time to add the section dealing with Ishi's life in the museum, Lewis went immediately to Christopher Trumbo. "It was impossible to go to anybody else," says Lewis. "Chris is so close to his dad. He sounds just like him."

For Christopher, who finished the script of "Papillon" after his father had a lung removed, "Ishi" is a special opportunity. Up to now, the 37-year-old Trumbo has written scripts for such television series as "Ironside" and "Army Prentiss" and "The Don Is Dead." It isn't much, he is the first to acknowledge.

"Oddly enough, and it's terrible to say, but Ishi is the first thing I've really felt strongly about. Being a commercial writer is difficult to the extent that you must write in order to earn your living and the kinds of projects you get offered are not necessarily the finest things in the world.

"But 'Ishi' is different, 'Ishi' is not trying to compel attention by tricks. 'Ishi' is almost plotless. In other words we are driven more by events, history and human emotion than we are by structuring it cleverly. We don't necessarily have great moments of tension at commercial breaks because the story doesn't allow for that."

The idea that "Ishi" is different seems to have affected everyone involved in its production from director Robert Miller ("The Heart Is a Lonely Hunter") to the assistants in the trucks. The eight-weeks shooting schedule was delayed by a winter that was the second rainiest in the 77 years since Ishi came in from Waganupa, but the spirits of the company are high. The best-known actor among them is Dennis Weaver, who plays a composite anthropolotist known as Fuller. The Indians were chosen after interviews with hundreds of applicants at various location in the Southwest. Three of them, including a student at Brigham Young University who has never acted before, play Ishi at different stages of his life.

The movie may not please all readers of the original book. Kroeber, the author, says she wasn't consulted and doesn't plan to watch the television production. And Lewis is careful to say this work is not a documentary, but "a film based on the book."

The film gives Ishi a somewhat better English vocabulary than he actually commanded and allows him to pronounce the consonant "f," which was absent from the Yahi language and unpronounceable to the real Ishi. Eloy Phil Casados, one of the actors who plays Ishi, is bothered by the omission from the script of an incident which occurred after Ishi's death, when his brain was removed in an autopsy and preserved in defiance of his religious belief after the unity of body and spirit after death. The story of the autopsy, however, is also omitted in the second Kroeber book on which the screenplay is based.

On other historical scores. "Ishi" acquits itself well. Documentary it may not be, but the massacre of the Yahis depicted in the television film is a historically accurate re-creation of the Three Knolls Massacre, the most devastating of several mass killings of the tribe. The only omissions here are the scalpings and other atrocities committed by the killers, which not even the most permissive television code would allow.

Fuller is fictional, but the bow-hunting trip he takes to Yahi country with his son and Ishi recreates a similar journey that the real Ishi made with a doctor, his son and anthropologists Kroeber and Thomas Waterman.

"The book and the movie are different mediums," says Casados. "The truth lies between them. What we can do on this picture is simply to try and tell the story the best we can."

That perception of the world which conquered Ishi pervades the film and yields a terrible sadness. It is the sadness of the loss of a people, a loss expressed by Ishi as he buries his mother in their ancestral cave and prepares to enter the world of the whites.

As Ishi runs down the hill to Oroville we hear the voice of his mind saying: "It is finished, the long search for the lost ones. They found the trail through the ice and are at last in the land of the dead.Now there is nothing to wait for in this empty land."