There are acting careers; and then there are actors whose lives transcend the notion of a career. Robert Duvall fits into the latter category. What we've seen of him speaks more of an artist following inevitable inner promptings than a performer looking for the next big break. In fact, he probably owns a permanent niche in the lonely league of actors who have built a solid, hard-to-ignore body of work. Consequently, early examples of this work carry more than passing interest: They afford an opportunity to watch a man assembling his craft.
Tomorrow, the 1972 film based on a William Faulkner story (PBS, Monday, Dec. 17, 9-11 p.m.), gives us just such an opportunity, although the product may not measure up to Duvall's later accomplishments.
This is the film that earned Duvall his first tidal wave of critical praise. The film, part of the ''American Playhouse'' series, offers the added interest of being an early screen collaboration between Duvall and writer Horton Foote. Before this project, Foote recommended Duvall in 1963 for the movie that gave him his big break, ''To Kill a Mockingbird.'' Foote also wrote ''Tender Mercies, '' for which both he and Duvall earned Oscars. They are now working on a project that will cast Duvall as a 78-year-old convict.
In ''Tomorrow,'' you see Duvall's serious concern for acting as a way to lend honor and dignity to the lives of those who find these commodities in short supply.
The story watches impassively as Jackson Fentry (Duvall) - a taciturn, dirt-poor man of the Southern hills - finds and shelters Sarah Eubanks (Olga Bellin). Mrs. Eubanks is in the late stages of pregnancy and has been abandoned. She happens across Fentry's isolated shack and into his life. Before long, he is asking her to marry him; but she has been so wrung out by her hard life that marriage seems impossible.
Nobody talks much in the hollows where this story takes place, least of all Fentry. The spare, severe story line is mirrored in almost monosyllabic dialogue. This must have been part of the attraction for Foote, Duvall, and director Joseph Anthony. They set out to create a realistic black-and-white telling of the unadorned, hard-edged life faced by such people. The impulse is close to that behind ''Tender Mercies'' and even ''Angelo, My Love,'' the film about gypsy life in this countrywhich Duvall scripted and directed, and for which he used nonprofessional actors to create the world they know best.
This impulse is apparently still strong with Duvall, who has said that he wants to make a ''Tobacco Road'' type of film using real ''Okies'' and their descendants. Part of the reason for making such a film, he says, is to make up for what he sees as the gross distortions and stereotypes to be found in the Hollywood film classic of Steinbeck's novel, starring Henry Fonda.
So here in ''Tomorrow,'' we see a much younger Duvall wrestling - in a role he is said to consider his best - to make of himself the kind of unpretentious material he sees in common folk.
And he has certainly assembled the various artifacts that could bring this type of character to life. His stiff manner, plastered hair, and deliberately impassive view of life make all kinds of sense here. But while the working parts of this characterization are all together in one place, they don't always mesh in a convincing entity. His voice and accent are authentic to the place and time , but not always to Duvall himself.
During his career, Duvall has learned the small technical things that add needed artifice to honesty. Most of them are probably instinctive at this point. But they are there. A more mature Duvall might have, for instance, modified that voice and speaking style. He might have avoided some mannerisms that - although authentic - just wouldn't play.
In all fairness, neither the script nor the supporting work of Olga Bellin gives a totally convincing portrait of life in these hollows. And this in part has to do with the nature of the story. Faulkner wrote interior drama with all kinds of exterior ambiance. His elliptical plot lines were generally intended to negotiate a reader through the close quarters his characters inhabit. But very little of this works well as film, so that ''Tomorrow'' tends to be static when it means to be moving and simple.
One watches from afar, like the indifferent earth.
None of this has stopped the film from acquiring a small but loyal following, ever since its theatrical release 12 years ago. And, if only for the fact that it provides an opportunity to watch a craftsman of Duvall's caliber put things together, it still holds enduring interest.