Shirley MacLaine--movie star, political activist, travel reporter, and now spiritual teacher of the masses--turns so far into herself and takes so many atavistic star turns in "Out on a Limb" that reading her is like watching an ice skater's death spiral. Discussions of cosmic justice, past-life recall, channeling, vibration frequencies, UFOs and astral planes come whirling by so fast and so indiscriminately whipped up that it all becomes a blur. And MacLaine, a woman of considerable intelligence and charm, lands right on her reincarnated rear.

Her preliminary exercise, which serves as both a taking-off point and counterpoint for her spiritual safari, is her ambivalent account of her secret affair with a well-known married British socialist, identified as "Gerry." MacLaine describes Gerry as "a bear who needed to hug the world," a handsome klutz who, when he left MacLaine's dressing room at the Palladium, walked directly into her closet. (This is an ongoing and symbolic joke, as Gerry continues to stumble into closets all over the world.) In Sweden, MacLaine gives him his first body massage; in Hawaii he learns, under her tutelage, how to body surf--obviously "some kind of sensual dynamic was operating."

Gerry is guilt-ridden ("I'm upset at pleasure") and caught between his wife--a strict Marxist who doesn't even like it when he wears fur gloves in the winter--his children, a political career that could not support scandal, and the affair that forces both MacLaine and Gerry into hypocritical positions, anathema to both of them.

Between assignations, MacLaine goes off to think on the beaches of Malibu, eating peaches with David, her spiritual mentor. Then she's off to the Calabasas mountains at "The Ashram," which is "a kind of rough-and-ready, spiritually involved health camp ('spa' to those who had a lot of money)." Armed with note pads and tape recorders, MacLaine listens as her friends raise some exotically heavy questions ("You mean, like why we are alive and what is our purpose?").

She presents herself as an interested skeptic, but readers of her first two books are already aware of her fascination with identity, mysticism, and oriental philosophy. Corkers abound with embarrassing regularity: "I mean that six million Jews did not really die. Only their bodies have." Or: "For example, how do you think Moses wrote of the creation of the world if he hadn't been plugged in psychically?" The long dialogue-soaked chapters read like taped transcripts with apparently little editing brought to play.

At "The Ashram" she continues her dialogues with Cat, a devotee of Sai Baba, an avatar in India. Cat explains to MacLaine: "I feel my own spiritual light and I'm in love with that and I don't need anything else." MacLaine deadpans: "Jesus, I thought if I could be in love with my own spiritual light, it would save me a lot of plane trips and a lot of grief, too."

She visits with two trance channelers (whose bodies are used to channel spirits through), where she learns that MacLaine and Gerry had been married in a previous life and MacLaine's "twin soul" turns out to be David. (They were separated at the time of the Big Bang.)

Talking to Peter Sellers during the filming of "Being There," she finds a sympathetic ear. He admits to having an out-of-body experience once when he almost died. A year and a half later, MacLaine jumped up and said, "Something has happened to Peter Sellers." A phone rang and a reporter told MacLaine that Sellers had died.

With MacLaine's liaison with Gerry on the wane ("my attitude toward his reluctance to express any interest in my concern for expanded consciousness was one of growing impatience"), she delves into the literature with a vengeance, searching, searching like a mad woman for The Truth--a kind of Joan Didion heroine on speed. She takes in everything underneath the astrological sun, not really separating genius from crackpot, or sifting out quality and credibility. Soon her "bookshelves began to bulge with esoteric metaphysical material." The chapters become mishmash, a regular Tower of Babel with beliefs of Pythagoras, Plato, and Voltaire mixed in with Von Daniken and Cayce. MacLaine is under the unfortunate impression that all the thinking is of a piece; and since not unproven, she keeps an open mind to everything.

MacLaine has not honed or shaped her raw material in any organized or coherent fashion. Nor do the transcripts, research and doodling leave any time for perspective and reflection. MacLaine jumps from one subject to another with such dazzling mecurialism and enthusiasm that one laughs aloud when Bella Abzug pipes up and says, "Jesus, now what?"

Only a really splendid travel piece--MacLaine and David on a mountain retreat in Peru--has the kind of comfortable, soft-sell mysticism that MacLaine writes about with exacting intoxication (as she did earlier with the exotic locales in "Don't Fall off the Mountain" and "You Can Get There From Here"). But the mood is shattered when David announces that he was once in love with a woman from another planet. MacLaine is startled but doesn't rule it out.

"Out on a Limb" puts the gutsy MacLaine out on a limb all right, but why couldn't her book have been better written, more balanced, less drenched in didactics? One small consolation may be that in the actress-writer's next life she can get it right.