Madame Gioconda read the note, let it fall to the floor.

'Hector? Those lawyers poison him. He's surrounded by them, I think they steal all my telegrams to him. Of course Hector had a complete breakdown on the spectaculars. Imagine, Mangon, what a scoop for him, a sensation! 'The great Gioconda will appear on television!' Not just some moronic bubblegum girl, but the Gioconda in person.'

Exhausted by this vision Madame Gioconda sank back into her cushion, blowing smoke limply through the holder.

Mangon wrote: Contract?

Madame Gioconda frowned at the note, then pierced it with the glowing end of her cigarette.

'I am having a new contract drawn up. Not for the mere 300,000 I was prepared to take at first, not even 500,000. For each show I shall now demand precisely one million dollars. Nothing less! Hector will have to pay for ignoring me. Anyway, think of the publicity value of such a figure. Only a star could think of such vulgar extravagance. If he's short of cash he can sack all those lawyers. Or devalue the dollar, I don't mind.'

Madame Gioconda hooted with pleasure at the prospect. Mangon nodded, then scribbled another message.

Be practical.

Madame Gioconda ground out her cigarette. 'You think I'm raving, don't you, Mangon? "Fantastic dreams, milliondollar contracts, poor old fool." But let me assure you that Hector will be only too eager to sign the contract. And I don't intend to rely solely on his good judgement as an impresario.' She smirked archly to herself.

What else?

Madame Gioconda peered round the darkened stage, then lowered her eyes.

'You see, Mangon, Hector and I are very old friends. You know what I mean, of course?' She waited for Mangon, who had swept out a thousand honeymoon hotel suites, to nod and then continued: 'How well I remember that first season at Bayreuth, when Hector and I..

Mangon stared unhappily at his feet as Madame Gioconda outlined this latest venture into blackmail. Certainly she and LeGrande had been intimate friends the cuttings scattered around the stage testified frankly to this. In fact, were it not for the small monthly cheque which LeGrande sent Madame Gioconda she would long previously have disintegrated. To turn on him and threaten ancient scandal (LeGrande was shortly to enter politics) was not only grotesque but extremely dangerous, for LeGrande was ruthless and unsentimental. Years earlier he had used Madame Gioconda as a steppingstone, reaping all the publicity he could from their affair, then abruptly kicking her away.

Mangon fretted. A solution to her predicament was hard to find. Brought about through no fault of her own, Madame Gioconda's decline was all the harder to bear. Since the introduction a few years earlier of ultrasonic music, the human voice indeed, audible music of any type had gone completely out of fashion. Ultrasonic music, employing a vastly greater range of octaves, chords and chromatic scales than are audible by the human ear, provided a direct neural link between the sound stream and the auditory lobes, generating an apparently sourceless sensation of harmony, rhythm, cadence and melody uncontaminated by the noise and vibration of audible music. The rescoring of the classical repertoire allowed the ultrasonic audience the best of both worlds. The majestic rhythms of Beethoven, the popular melodies of Tchaikovsky, the complex fugal elaborations of Bach, the abstract images of Schoenberg all these were raised in frequency above the threshold of conscious audibility. Not only did they become inaudible, but the original works were rescored for the much wider range of the ultrasonic orchestra, became richer in texture, more profound in theme, more sensitive, tender or lyrical as the ultrasonic arranger chose.

The first casualty in this changeover was the human voice. This alone of all instruments could not be rescored, because its sounds were produced by nonmechanical means which the neurophonic engineer could never hope, or bother, to duplicate.

The earliest ultrasonic recordings had met with resistance, even ridicule. Radio programmes consisting of nothing but silence interrupted at halfhour intervals by commercial breaks seemed absurd. But gradually the public discovered that the silence was golden, that after leaving the radio switched to an ultrasonic channel for an hour or so a pleasant atmosphere of rhythm and melody seemed to generate itself spontaneously around them. When an announcer suddenly stated that an ultrasonic version of Mozart's Jupiter Symphony or Tchaikovsky's Pathetique had just been played the listener identified the real source.

A second advantage of ultrasonic music was that its frequencies were so high they left no resonating residues in solid structures, and consequently there was no need to call in the soundsweep. After an audible performance of most symphonic music, walls and furniture throbbed for days with disintegrating residues that made the air seem leaden and tumid, an entire room virtually uninhabitable.

An immediate result was the swift collapse of all but a few symphony orchestras and opera companies. Concert halls and opera houses closed overnight. In the age of noise the tranquillizing balms of silence began to be rediscovered.

But the final triumph of ultrasonic music had come with a second development the shortplaying record, spinning at 900 r.p.m., which condensed the 45 minutes of a Beethoven symphony to 20 seconds of playing time, the three hours of a Wagner opera to little more than two minutes. Compact and cheap, SP records sacrificed nothing to brevity. One 30second SP record delivered as much neurophonic pleasure as a natural length recording, but with deeper penetration, greater total impact.

Ultrasonic SP records swept all others off the market. Sonic LP records became museum pieces only a crank would choose to listen to an audible fulllength version of Siegfried or the Barber of Seville when he could have both wrapped up inaudibly inside the same fiveminute package and appreciate their full musical value.

The heyday of Madame Gioconda was over. Unceremoniously left on the shelf, she had managed to survive for a few months vocalizing on radio commercials. Soon these too went ultrasonic. In a despairing act of revenge she bought out the radio station which fired her and made her home on one of the sound stages. Over the years the station became derelict and forgotten, its windows smashed, neon portico collapsing, aerials rusting. The huge eightlane flyover built across it sealed it conclusively into the past.

Now Madame Gioconda proposed to win her way back at stilettopoint.

Mangon watched her impassively as she ranted on nastily in a cloud of purple cigarette smoke, a large seedy witch. The phenobarbitone was making her drowsy and her threats and ultimatums were becoming disjointed.

'... memoirs too, don't forget, Hector. Frank exposure, no holds barred. I mean... damn, have to get a ghost. Hotel de Paris at Monte, lots of pictures. Oh yes, I kept the photographs.' She grubbed about on the couch, came up with a crumpled soap coupon and a supermarket pay slip. 'Wait till those lawyers see them. Hector , Suddenly she broke off, stared glassily at Mangon and sagged back.

Mangon waited until she was finally asleep, stood up and peered closely at her. She looked forlorn and desperate. He watched her reverently for a moment, then tiptoed to the rheostat mounted on the control panel behind the couch, damped down the lamp at Madame Gioconda's feet and left the stage.

He sealed the auditorium doors behind him, made his way down to the foyer and stepped out, sad but at the same time oddly exhilarated, into the cool midnight air. At last he accepted that he would have to act swiftly if he was to save Madame Gioconda.

Two.

Driving his sound truck into the city shortly after nine the next morning, Mangon decided to postpone his first call the weird NeoCorbusier Episcopalian Oratory sandwiched among the office blocks in the downtown financial sector and instead turned west on Mainway and across the park towards the whitefaced apartment batteries which reared up above the trees and lakes along the north side.

The Oratory was a difficult and laborious job that would take him three hours of concentrated effort. The Dean had recently imported some rare thirteenthcentury pediments from the Church of St Francis at Assisi, beautiful sonic matrices rich with seven centuries of Gregorian chant, overlaid by the timeless tolling of the Angelus. Mounted into the altar they emanated an atmosphere resonant with litany and devotion, a mellow, deeply textured hymn that silently evoked the most sublime images of prayer and meditation.

But at 50,000 dollars each they also represented a terrifying hazard to the clumsy soundsweep. Only two years earlier the entire north transept of Rheims Cathedral, rose window intact, purchased for a record 1,000,000 dollars and reerected in the new Cathedral of St Joseph at San Diego, had been drained of its priceless heritage of tonal inlays by a squad of illiterate soundsweeps who had misread their instructions and accidentally swept the wrong wall.

Even the most conscientious soundsweep was limited by his skill, and Mangon, with his auditory supersensitivity, was greatly in demand for his ability to sweep selectively, draining from the walls of the Oratory all extraneous and discordant noises coughing, crying, the clatter of coins and mumble of prayer leaving behind the chorales and liturgical chants which enhanced their devotional overtones. His skill alone would lengthen the life of the Assisi pediments by twenty years; without him they would soon become contaminated by the miscellaneous traffic of the congregation. Consequently he had no fears that the Dean would complain if he failed to appear as usual that morning.

Halfway along the north side of the park he swung off into the forecourt of a huge fortystorey apartment block, a glittering white cliff ribbed by jutting balconies. Most of the apartments were Superlux duplexes occupied by showbusiness people. No one was about, but as Mangon entered the hallway, sonovac in one hand, the marble walls and columns buzzed softly with the echoing chatter of guests leaving parties four or five hours earlier.

In the elevator the residues were clearer confident male tones, the sharp wheedling of querulous wives, soft negatives of amatory blondes, punctuated by countless repetitions of 'dahling'. Mangon ignored the echoes, which were almost inaudible, a dim insect hum. He grinned to himself as he rode up to the penthouse apartment; if Madame Gioconda had known his destination she would have strangled him on the spot.

Ray Alto, doyen of the ultrasonic composers and the man more than any other responsible for Madame Gioconda's decline, was one of Mangon's regular calls. Usually Mangon swept his apartment once a week, calling at three in the afternoon. Today, however, he wanted to make sure of finding Alto before he left for Video City, where he was a director of programme music.

The houseboy let him in. He crossed the hall and made his way down the black glass staircase into the sunken lounge. Wide studio windows revealed an elegant panorama of park and midtown skyscrapers.

A whiteslacked young man sitting on one of the long slab sofas Paul Merrill, Alto's arranger waved him back.

'Mangon, hold on to your dive breaks. I'm really on reheat this morning.' He twirled the ultrasonic trumpet he was playing, a tangle of stops and valves from which half a dozen leads trailed off across the cushions to a cathode tube and tone generator at the other end of the sofa.

Mangon sat down quietly and Merrill clamped the mouthpiece to his lips. Watching the ray tube intently, where he could check the shape of the ultrasonic notes, he launched into a brisk allegretto sequence, then quickened and flicked out a series of brilliant arpeggios, stripping off high P and Q notes that danced across the cathode screen like frantic eels, fantastic glissandos that raced up twenty octaves in as many seconds, each note distinct and symmetrically exact, tripping off the tone generator in turn so that escalators of electronic chords interweaved the original scale, a multichannel melodic stream that crowded the cathode screen with exquisite, flickering patterns. The whole thing was inaudible, but the air around Mangon felt vibrant and accelerated, charged with gaiety and sparkle, and he applauded generously when Merrill threw off a final dashing riff.

'Flight of the Bumble Bee,' Merrill told him. He tossed the trumpet aside and switched off the cathode tube. He lay back and savoured the glistening air for a moment. 'Well, how are things?'

Just then the door from one of the bedrooms opened and Ray Alto appeared, a tall, thoughtful man of about forty, with thinning blonde hair, wearing pale sunglasses over cool eyes.

'Hello, Mangon,' he said, running a hand over Mangon's head. 'You're early today. Full programme?' Mangon nodded. 'Don't let it get you down.' Alto picked a dictaphone off one of the end tables, carried it over to an armchair. 'Noise, noise, noise the greatest single diseasevector of civilization. The whole world's rotting with it, yet all they can afford is a few people like Mangon fooling around with sonovacs. It's hard to believe that only a few years ago people completely failed to realize that sound left any residues.'

'Are we any better?' Merrill asked. 'This month's Transonics claims that eventually unswept sonic resonances will build up to a critical point where they'll literally start shaking buildings apart. The entire city will come down like Jericho.'

'Babel,' Alto corrected. 'Okay, now, let's shut up. We'll be gone soon, Mangon. Buy him a dnink, would you, Paul.'

Merrill brought Mangon a coke from the bar, then wandered off. Alto flipped on the dictaphone, began to speak steadily into it. 'Memo 7: Betty, when does the copyright on Stravinsky lapse? Memo 8: Betty, file melody for projected nocturne: L, L sharp, BB, Y flat, Q, VT, L, L sharp. Memo 9: Paul, the bottom three octaves of the ultratuba are within the audible spectrum of the canine ear congrats on that SP of the Anvil Chorus last night; about three million dogs thought the roof had fallen in on them. Memo 10: Betty ' He broke off, put down the microphone. 'Mangon, you look worried.'

Mangon, who had been lost in reverie, pulled himself together and shook his head.

'Working too hard?' Alto pressed. He scrutinized Mangon suspiciously. 'Are you still sitting up all night with that Gioconda woman?'

Embarrassed, Mangon lowered his eyes. His relationship with Alto was, obliquely, almost as close as that with Madame Gioconda. Although Alto was brusque and often irritable with Mangon, he took a sincere interest in his welfare. Possibly Mangon's muteness reminded him of the misanthropic motives behind his hatred of noise, made him feel indirectly responsible for the act of violence Mangon's mother had committed. Also, one artist to another, he respected Mangon's phenomenal auditory sensitivity.

'She'll exhaust you, Mangon, believe me.' Alto knew how much the personal contact meant to Mangon and hesitated to be overcritical. 'There's nothing you can do for her. Offering her sympathy merely fans her hopes for a comeback. She hasn't a chance.'

Mangon frowned, wrote quickly on his wristpad: She WILL sing again!

Alto read the note pensively. Then, in a harder voice, he said: 'She's using you for her own purposes, Mangon. At present you satisfy one whim of hers the neurotic headaches and fantasy applause. God forbid what the next whim might be.'

She is a great artist.

'She was,' Alto pointed out. 'No more, though, sad as it is. I'm afraid that the times change.'

Annoyed by this, Mangon gritted his teeth and tore off another sheet.

Entertainment, perhaps. Art, No!

Alto accepted the rebuke silently; he reproved himself as much as Mangon did for selling out to Video City. In his four years there his output of original ultrasonic music consisted of little more than one nearly finished symphony aptly titled Opus Zero shortly to receive its first performance, a few nocturnes and one quartet. Most of his energies went into programme music, prestige numbers for spectaculars and a mass of straight transcriptions of the classical repertoire. The last he particularly despised, fit work for Paul Merrill, but not for a responsible composer.

He added the sheet to the two in his left hand and asked: 'Have you ever heard Madame Gioconda sing?'

Mangon's answer came back scornfully: No! But you have. Please describe.

Alto laughed shortly, tore up his sheets and walked across to the window.

'All right, Mangon, you've made your point. You're carrying a torch for art, doing your duty to one of the few perfect things the world has ever produced. I hope you're equal to the responsibility. La Gioconda might be quite a handful. Do you know that at one time the doors of Covent Garden, La Scala and the Met were closed to her? They said Callas had temperament, but she was a girl guide compared with Gioconda. Tell me, how is she? Eating enough?'

Mangon held up his coke bottle.

'Snow? That's tough. But how does she afford it?' He glanced at his watch. 'Dammit, I've got to leave. Clean this place out thoroughly, will you. It gives me a headache just listening to myself think.'

He started to pick up the dictaphone but Mangon was scribbling rapidly on his pad.

Give Madame Gioconda a job.

Alto read the note, then gave it back to Mangon, puzzled. 'Where? In this apartment?' Mangon shook his head. 'Do you mean at V. C.? Singing?'

When Mangon began to nod vigorously he looked up at the ceiling with a despairing groan. 'For heaven's sake, Mangon, the last vocalist sang at Video City over ten years ago. No audience would stand for it. If I even suggested such an idea they'd tear my contract into a thousand pieces.' He shuddered, only halfplayfully. 'I don't know about you, Mangon, but I've got my ulcer to support.'

He made his way to the staircase, but Mangon intercepted him, pencil flashing across the wristpad.

Please. Madame Gioconda will start blackmail soon. She is desperate.

Must sing again. Could arrange makebelieve programme in research studios. Closed circuit.

Alto folded the note carefully, left the dictaphone on the staircase and walked slowly back to the window.

'This blackmail. Are you absolutely sure? Who, though, do you know?' Mangon nodded, but looked away. 'Okay, I won't press you. LeGrande, probably, eh?' Mangon turned round in surprise, then gave an elaborate parody of a shrug.

'Hector LeGrande. Obvious guess. But there are no secrets there, it's all on open file. I suppose she's just threatening to make enough of an exhibition of herself to block his governorship.' Alto pursed his lips. He loathed LeGrande, not merely for having bribed him into a way of life he could never renounce, but also because, once having exploited his weakness, LeGrande never hesitated to remind Alto of it, treating him and his music with contempt. If Madame Gioconda's blackmail had the slightest hope of success he would have been only too happy, but he knew LeGrande would destroy her, probably take Mangon too.

Suddenly he felt a paradoxical sense of loyalty for Madame Gioconda. He looked at Mangon, waiting patiently, big spaniel eyes wide with hope.

'The idea of a closed circuit programme is insane. Even if we went to all the trouble of staging it she wouldn't be satisfied. She doesn't want to sing, she wants to be a star. It's the trappings of stardom she misses the cheering galleries, the piles of bouquets, the green room parties. I could arrange a halfhour session on closed circuit with some trainee technicians a few straight selections from Tosca and Butterfly, say, with even a sonic piano accompaniment, I'd be glad to play it myself but I can't provide the gossip columns and theatre reviews. What would happen when she found out?'

She wants to SING.

Alto reached out and patted Mangon on the shoulder. 'Good for you. All right, then, I'll think about it. God knows how we'd arrange it. We'd have to tell her that she'll be making a surprise guest appearance on one of the big shows that'll explain the absence of any programme announcement and we'll be able to keep her in an isolated studio. Stress the importance of surprise, to prevent her from contacting the newspapers... Where are you going?'

Mangon reached the staircase, picked up the dictaphone and returned to Alto with it. He grinned happily, his jaw working wildly as he struggled to speak. Strangled sounds quavered in his throat.

Touched, Alto turned away from him and sat down. 'Okay, Mangon,' he snapped brusquely, 'you can get on with your job. Remember, I haven't promised anything.' He flicked on the dictaphone, then began: 'Memo 11: Ray...'

Three.

It was just after four o'clock when Mangon braked the sound truck in the alley behind the derelict station. Overhead the traffic hammered along the flyover, dinning down on to the cobbled walls. He had been trying to finish his rounds early enough to bring Madame Gioconda the big news before her headaches began. He had swept out the Oratory in an hour, whirled through a couple of movie theatres, the Museum of Abstract Art, and a dozen private calls in half his usual time, driven by his almost overwhelming joy at having won a promise of help from Ray Alto.

He ran through the foyer, already fumbling at his wristpad. For the first time in many years he really regretted his muteness, his inability to tell Madame Gioconda orally of his triumph that morning.

Studio 2 was in darkness, the rows of seats and litter of old programmes and icecream cartons reflected dimly in the single light masked by the tall flats. His feet slipped in some shattered plaster fallen from the ceiling and he was out of breath when he clambered up on to the stage and swung round the nearest flat.

Madame Gioconda had gone!

The stage was deserted, the couch a rumpled mess, a clutter of cold saucepans on the stove. The wardrobe door was open, dresses wrenched outwards off their hangers.

For a moment Mangon panicked, unable to visualize why she should have left, immediately assuming that she had discovered his plot with Alto.

Then he realized that never before had he visited the studio until midnight at the earliest, and that Madame Gioconda had merely gone out to the supermarket. He smiled at his own stupidity and sat down on the couch to wait for her, sighing with relief.

As vivid as if they had been daubed in letters ten feet deep, the words leapt out from the walls, nearly deafening him with their force.

'You grotesque old witch, you must be insane! You ever threaten me again and I'll have you destroyed! LISTEN, you pathetic , Mangon spun round helplessly, trying to screen his ears. The words must have been hurled out in a paroxysm of abuse, they were only an hour old, vicious sonic scars slashed across the immaculately swept walls.

His first thought was to rush out for the sonovac and sweep the walls clear before Madame Gioconda returned. Then it dawned on him that she had already heard the original of the echoes in the background he could just detect the muffled rhythms and intonations of her voice.

All too exactly, he could identify the man's voice.

He had heard it many times before, raging in the same ruthless tirades, when deputizing for one of the soundsweeps, he had swept out the main boardroom at Video City.

Hector LeGrande! So Madame Gioconda had been more desperate than he thought.

The bottom drawer of the dressing table lay on the floor, its contents upended. Propped against the mirror was an old silver portrait frame, dull and verdigrised, some cotton wool and a tin of cleansing fluid next to it. The photograph was one of LeGrande, taken twenty years earlier. She must have known LeGrande was coming and had searched out the old portrait, probably regretting the threat of blackmail.

But the sentiment had not been shared.

Mangon walked round the stage, his heart knotting with rage, filling his ears with LeGrande's taunts. He picked up the portrait, pressed it between his palms, and suddenly smashed it across the edge of the dressing table.