''The Sheltering Sky'' is more interesting than it deserves to be. Done by Bernardo Bertolucci on locations in North Africa, the film is strangely fascinating, in large part if not throughout. Its basic failing is that it should end long before it does.
If you've read the book, you have the advantage. If you haven't, you might wonder what the final segment is about. Bertolucci, who co-authored the script, is obviously trying for something spiritual here, the effect of the North African culture on the leading female character, but it may be all too special, more mysterious than mystical. The final portion of the film plays like a PBS documentary without the narration, something it sorely needs.
''The Sheltering Sky'' is based on the book by Paul Bowles, who is described as an existential poet and novelist. He and his wife, Jane, moved to North Africa after World War II. He wrote about their experiences in the book, which was published in 1949 and became a ''cult classic.''
You can believe that material of this sort, self-contemplative writing, would make it as a cult novel. It has a harder time making it as a film.
Of course, we all know Bertolucci. We know that when he does a film, it is going to be long on mood and milieu. We also know that the film is going to be very slow, very exotic, and ''The Sheltering Sky'' is both those things.
Its principal characters are an American composer, his playwright wife and their friend, a wealthy young man who seems to have nothing on his mind, save the wife of his friend.
Their trek begins in Tangier then moves to the Sahara, where it becomes a logistical marvel. You wonder, as you watch the film, how Bertolucci managed to move his crews across this terrain, how he managed to film as much as he did, how he managed to persuade the natives to work for him.
The lead characters, Port and Kit Moresby, have been married for 10 years, but they don't have much going for them, as a team. She is clearly disenchanted. He is something of a fool. At one point, he wanders off to visit a brothel, dangerous business, even in the late '40s. Later, he loses his passport, and when he does, you wonder why this man has been allowed to travel without a leash.
The performances are strong. John Malkovich is the would-be composer, Debra Winger is his wife, and Campbell Scott (''Longtime Companion'') is their friend. Eric Vu-An, a French-Vietnamese ballet dancer, is the leader of the Tauregs, a North African people who seem to adopt the American woman.
The initiation, however, is strange. At one point, the Tauregs lock the woman in her room where she is visited by the leader of the group, a young man who takes the woman to bed.
She complies, readily. Kit Moresby, it seems, is decades ahead of her time. She'd be very much at home in a film about the '60s.
This is the portion that mystifies, and no one attempts to explain. Bowles might, and should. Bertolucci uses him. He serves as a kind of one-man Greek chorus who comments from the sidelines Tangier. His remarks, however, are more poetic than pointed.
Bertolucci is quoted as saying that he wanted to make a movie that was not about literature but life. Unfortunately, the latter portion of his film is too prosy for its own good.
''Sheltering Sky,'' two hours and 20 minutes long, is a visually stunning, geographical marvel. Its trouble is those dry patches, some of which are big enough to dwarf the Sahara.
** An American husband and wife, their marriage falling apart, wander North Africa after World War II.
CAST: Debra Winger, John Malkovich, Campbell Scott, Jill Bennett, Timothy Spall, Eric Vu-An.
DIRECTOR: Bernardo Bertolucci
RATING: R (sex, nudity)
RUNNING TIME: 140 minutes