A vast pool of unreleased features has been accumulating over the past decade, inspiring occasional efforts at salvage. The same independent company that recently resurrected "The Wicker Man" has now uncovered a far more valuable Gothic artifact, "The Haunting of Julia," which begins an American premiere engagement today at the K-B MacArthur.

Derived from Peter Straub's first novel, "Julia," the movie was an Anglo-Canadian production shot in London and Montreal late in 1976. It dropped out of sight following an unsuccessful debut in London in 1978. Straub's subsequent renown as a bestselling specialist in neo-Gothic fiction ("Ghost Story") and the current vogue for horror movies may permit this impressively chilling blend of psychological and supernatural terror -- directed with ominous, often voluptuous control by Richard Loncraine -- to find an appreciative public.

Loncraine and the screenwriters, Dave Humphries and Harry Bromley Davenport, have contrived an astute compression and rearrangement of the Straub hocus-pocus. The film succeeds in fusing the scariest elements from "Don't Look Now" and "repulsion": the traumatic inpact of a child's death and the surrender to schizophrenic derangement. Even when the details degenerate into conventional spooky hokum, they benefit from the authenticity of the fears being exploited -- parental anxiety and the fear of madness.

A disarming breakfast scene is violently disrupted when an accident costs the life of a little girl, Katie Lofting, the 9-year-old daughter of a prosperous London couple, Julia and Magnus Lofting, portrayed by Mia Farrow and Keir Dullea. The incident occurs with truly terrifying suddenness, the parents prove ineffectual (and may have intensified Katie's suffering with their efforts) and the sense of loss and helplessness is overwhelming. You don't doubt for a moment that the Loftings have become a haunted couple.

Julia emerges from several months of hospital care apparently calm but alienated from her husband. Determined to live alone, she impulsively buys a huge old furnished house in Kensington. While Julia stays in contact with her sister-in-law, Lily, played by Jill Bennett, and a close friend named Mark, an antique store proprietor impersonated with droll charm by Tom Conti, she refuses to speak to Magnus. It's obvious that he has failed her in a way that she can't forgive; and her resentment may be justified, not so much by his failure to prevent Katie's death as his failure to feel it as strongly as she.

The new house is revealed to be a torment. Julia's precarious nerves are immediately jangled by fleeting impressions of a blond child resembling Katie in a nearby park and in the mirrors of the house. A brisk, matronly medium, smartly played by Anna Wing, is given the willies after an evening's exposure to Julia's new surroundings. Eventually, Julia learns that she has acquired a murder house, and the knowledge holds her spellbound -- determined to uncover the facts behind the murder and also enthralled by the ghost child.

Straub complicated his plot fulsomely by adding a bad-seed motif and an incest motif to the already combustible mixture of grief-stricken mother, phantom and haunted house. The movie is content to simplify matters while capitalizing on the expressive resources offered by actors and a pictorial medium. Julia's neurotic susceptibility is authenticated far more effectively by Mia Farrow's fragile, high-strung presence than any of the novelist's psychological sketchwork. In a similar respect, the haunted house lives in the movie in a form that simplifies and surpasses Straub's prose creation. Loncraine envelops us in a setting that feels claustrophobic and maddening, inviting apprehension from shadowy corners, hidden recesses and alarming fixtures, especially mirrors and those oddly uncontrollable room heaters that keep staring at us with a scalding red eye.

This mystery keeps you guessing right through the fadeout. Depending on your frame of mind, it would be consistent with the evidence to perceive Julia as a victim of insanity or a victim of literal ghostly malice. Loncraine sustains the tightrope walk between madness and supernaturalism. It could be one, it could be the other, and who's to say which is scarier?

There is a weak link in the cast: Keir Dullea as Magnus. The character in the novel suggests a powerful, even brutish actor like Oliver Reed. But at this stage of his career, Dullea is not so much a Magnus as a minus, and one suspects that his casting owes more to the Canadian tax-shelter aspects of the financing than the elemental sexual conflict Straub wanted to suggest. On the other hand, the role of Mark is much improved by tailoring it to Tom Conti's humorous talents, and the heroine's researches into the dreadful past rationalize splendid supporting bits by Robin Gammel, Cathleen Nesbitt, Mary Morris, Arthur Howard, Damaris Hayman, Edward Hardwicke and several other expert players.

Whether she likes it or not, Mia Farrow may be destined to be recalled as a queen of the Gothics. One could mount a miniature but convincing festival already on the strength of "Rosemay's Baby," "Secret Ceremony," "See No evil," "Death on the Nile" and "The Haunting of Julia." In a sense she lends herself all too easily to sinister exploitation, appearing exceptionally vulnerable as a victim and shockingly eccentric as a victimizer. Nevertheless, it's impossible to imagine anyone being better than Farrow as the child-women at the center of the terrors conjured up by a "rosemay's Baby" or "Haunting of Julia." The sight of her haunted has a way of leaving you haunted.