Iain Banks, author of "The Wasp Factory," a celebrated tale of childhood mayhem, has now concocted a brilliant mind-boggler of a novel that is part sexual melodrama, part tale of madness and part futuristic allegory. Indeed, "Walking on Glass" is really three separate novellas, each with its own genre, characters and internal logic, each gradually intersecting with the others in odd and malevolent ways.

Not only do images from one tale find their way into another -- a mutilated cat drifts from Plot 2 to Plot 1, furnishing the latter's grim epiphany; talking crows flap through Plot 3 into Plot 2, transforming the former's meaning -- but all three also involve devious games that lead the players toward apocalyptic insights. It is a measure of Banks' ingenuity that each story resonates even though their connections give the novel its real kick.

The most gripping of the three plots is the first, a femme fatale tale with enough perverse twists and dark corners to satisfy our appetite for a "good read" in an otherwise experimental novel. Graham Park, the hero, is an innocent, likable Londoner of 20 who is desperately in love with a seductively mysterious woman. She is having an affair with a biker who never seems to remove his crash helmet. This shadowy figure, who looks like "Darth Vader without the cloak," turns out to be a far more formidable rival than Graham imagined, just as the woman he is obsessed with travels beyond "all the most sexist caricatures of female deception" into a realm of pure evil.

The most comic narrative, told from the point of view of a paranoid psychotic, has the same virtuosity in rendering mental disorder that Banks demonstrated with such peculiar grace in "The Wasp Factory." Steven Grout, the hero, is "being victimised against" by everyone: His employer is out to zap him with a Microwave Gun; the unemployment officer is training a more "subtly fiendish" beam on him; his entire life is "part punishment, part test" at the hands of godlike tormentors.

The writing here has a savage, surreal humor culminating in a wacky set piece where Steven spends a whole chapter trying to get past his lonely landlady: "Her hair was so tightly tied back at the rear of her skull that Grout swore the front strands, over her forehead, were being pulled out by the roots, and that the tautened skin so produced was thus responsible for the expression of malevolent surprise she wore; he had the impression that when Mrs. Short blinked her over-stretched eyelids didn't quite make it to the bottom of her eyes."

In the most overtly metaphysical plot, an old man and woman in a distant future are imprisoned in a castle of "claustrophobic infinity" where they must play endless, elaborate games (one-dimensional chess, Chinese Scrabble) as preludes to a riddle they can never answer, all as punishment for dimly remembered crimes against the state. Paradoxically, this "fantastic" plot, with its elves and talking birds, is the most ordinary. For once, Banks' tone is off; his sense of irony deserts him. He seems to know how derivative this scenario is -- he even has one character read from "The Castle" and "The Trial" and another mistakenly call someone Godot -- yet he allows characters to speak absurdist cliche's with jarring solemnity: "Know your strengths; don't attack when you're weak. That was his philosophy . . . That and an acceptance that life was basically absurd, unfair and -- ultimately -- pointless."

Yet even this story becomes fascinating when set against the others. The continually unfolding pleasure of "Walking on Glass" is the way each story forces the reader to constantly reinterpret the others, often in ways as ultimately unresolvable as the castle riddle. Does the fantasy tale finally collapse into Steven's hallucinations, for example -- or do the hallucinations turn out to be hideously accurate?

And the final spillover among the three plots leaves us with larger questions. Are the forces that direct our lives definitive, indifferent or parasitic? Do they in turn mirror the relationship of author to reader? Such questions are not new, but Banks' inventive way of raising them surely is.

Readers should be warned that this is not a chilling book like "The Wasp Factory" but rather a chilly one. Banks is more interested in bleak symmetry and perception this time than in character or story, and it's not for nothing that the castle is covered with snow, that Steven "shivers" in his mad euphoria, that Graham's final vision of "sex and violence, writ small like all our standard fantasies" is reflected in a spanking magazine sinking into a cold canal. The glass these characters are walking on is really ice.