'We're not supposed to take them off until the end!'

'It's been changed!'

'Has it? No one told me!' A short-necked giraffe next to him leaned sideways. 'What's that?'

'The big unmasking scene is now, apparently!'

'No one told me!'

'Yes, but when does anyone ever tell us anything? We're only the chorus. . . here, why is old Troublemaker wearing a monkey mask. . . ?' Nanny Ogg pirouetted past, cannoned into an elephant in evening dress and beheaded him by the trunk. She whispered: 'We're looking for the Ghost, see?'

'But. . . the Ghost is dead, isn't he?'

'Hard things to kill, ghosts,' said Nanny.

The whisper spread outwards from that point. There is nothing like a chorus for rumour. People who would not believe a High Priest if he said the sky was blue, and was able to produce signed affidavits to this effect from his white-haired old mother and three Vestal virgins, would trust just about anything whispered darkly behind their hand by a complete stranger in a pub. A cockatoo spun around and pulled the mask off a parrot. . . Bucket sobbed. This was worse than the day the buttermilk exploded. This was worse than the flash heat wave that had led a whole warehouse full of Lancre Extra Strong to riot. The opera had turned into a pantomime. The audience was laughing. About the only character still with a mask on was Senor Basilica, who was watching the struggling chorus with as much aloof amazement as his own mask could convey -and this, amazingly enough, was quite a lot. 'Oh, no. . .' moaned Bucket. 'We'll never live it down! He'll never come back! It'll be all over the opera circuit and no one will ever want to come here ever again!'

'Ever again wha'?' mumbled a voice behind him. Bucket turned. 'Oh, Senor Basilica,' he said. 'Didn't see you there. . . I was just thinking, I do hope you don't think this is typical!' Senor Basilica stared through him, swaying slightly from side to side. He was wearing a torn shirt. 'Summon. . .' he said. 'I'm sorry?'

'Summon. . . summon hit me onna head,' said the tenor. 'Wanna glassa water pliss. . .'

'But you're. . . just about. . . to. . . sing. . . aren't you?' said Bucket. He grabbed the stunned man by the collar to pull him closer, but this simply meant that he dragged himself off the floor, bringing his shoes about level with Basilica's knees. 'Tell me. . . you're out there. . . on the stage. . . please!!!' Even in his stunned state, Enrico Basilica a.k.a. Henry Slugg recognized what might be called the essential dichotomy of the statement. He stuck to what he knew. 'Summon bashed me inna corridor. . .' he volunteered. 'That's not you out there?' Basilica blinked heavily. “M not me?'

'You're going to sing the famous duet in a moment!!!' Another thought staggered through Basilica's abused skull. ”M I?' he said. "S good. . . 'll look forwa' to that. Ne'er had a chance to hear me befo'. . .' He gave a happy little sigh and fell full-length backwards. Bucket leaned against a pillar for support. Then his brow furrowed and, in the best traditions of the extended double-take, he stared at the fallen tenor and counted to one on his fingers. Then he turned towards the stage and counted to two. He could feel a fourth exclamation mark coming on any time now. The Enrico Basilica on stage turned his mask this way and that. Stage right, Bucket was whispering to a group of stage-hands. Stage left, André the secret pianist was waiting. A large troll loomed next to him. The fat red singer walked to centre-stage as the prelude to the duet began. The audience settled down again. Fun and games among the chorus was all very well-it might even be in the plot-but this was what they'd paid for. This was what it was all about.

Agnes stared at him as Christine walked towards him. Now she could see he wasn't right. Oh, he was fat, in a pillow-up-your-shirt sort of way, but he didn't move like Basilica. Basilica moved lightly on his feet, as fat men often do, giving the effect of a barely tethered balloon. She glanced at Nanny, who was also watching him carefully. She couldn't see Granny Weatherwax anywhere. That probably meant she was really close. The expectancy of the audience dragged at them all. Ears opened like petals. The fourth wall of the stage, the big black sucking darkness outside, was a well of silence begging to be filled up. Christine was walking towards him quite unconcerned. Christine would walk into a dragon's mouth if it had a sign on it saying 'Totally harmless, I promise you'. . . at least, if it was printed in large, easy-to- understand letters. No one seemed to want to do anything. It was a famous duet. And a beautiful one. Agnes ought to know. She'd been singing it all last night. Christine took the false Basilica's hand and, as the opening bars of the duet began, opened her mouth 'Stop right there!' Agnes put everything she could into it. The chandelier tinkled. The orchestra went silent in a skid of wheezes and twangs. In a fading of chords and a dying of echoes, the show stopped. Walter Plinge sat in the candlelit gloom under the stage, his hands resting on his lap. It was not often that Walter Plinge had nothing to do, but, when he did have nothing to do, he did nothing. He liked it down here. It was familiar. The sounds of the opera filtered through. They were muffled, but that didn't matter. Walter knew all the words, every note of music, every step of every dance. He needed the actual performances only in the same way that a clock needs its tiny little escapement mechanism; it kept him ticking nicely. Mrs Plinge had taught him to read using the old programmes. That's how he knew he was part of it all. But he knew that anyway. He'd cut what teeth he had on a helmet with horns on it. The first bed he could remember was the very same trampoline used by Dame Gigli in the infamous Bouncing Gigli incident. Walter Plinge lived opera. He breathed its songs, painted its scenery, lit its fires, washed its floors and shined its shoes. Opera filled up places in Walter Plinge that might otherwise have been empty. And now the show had stopped. But all the energy, all the raw pent-up emotion that is dammed up behind a show-all the screaming, the fears, the hopes, the desires-flew on, like a body hurled from the wreckage. The terrible momentum smashed into Walter Plinge like a tidal wave hitting a teacup. It propelled him out of his chair and flung him against the crumbling scenery. He slid down and rolled into a twitching heap on the floor, clapping his hands over his ears to shut out the sudden, unnatural silence. A shape stepped out of the shadows. Granny Weatherwax had never heard of psychiatry and would have had no truck with it even if she had. There are some arts too black even for a witch. She practised headology-practised, in fact, until she was very good at it. And though there may be some superficial similarities between a psychiatrist and a headologist, there is a huge practical difference. A psychiatrist, dealing with a man who fears he is being followed by a large and terrible monster, will endeavour to convince him that monsters

don't exist. Granny Weatherwax would simply give him a chair to stand on and a very heavy stick. 'Stand up, Walter Plinge,' she said. Walter stood up, staring straight ahead of him. 'It's stopped! It's stopped! It's bad luck to stop the show!' he said hoarsely. 'Someone better start it again,' said Granny. 'You can't stop the show! It's the show!'

'Yes. Someone better start it again, Walter Plinge.' Walter didn't appear to notice her. He pawed aimlessly through his stack of music and ran his hands through the drifts of old programmes. One hand touched the keyboard of the harmonium and played a few neurotic notes. 'Wrong to stop. Show must go on. . .'

'Mr Salzella is trying to stop the show, isn't he, Walter?' Walter's head shot up. He stared straight ahead of him. 'You haven't seen anything, Walter Plinge!' he said, in a voice so like Salzella's that even Granny raised an eyebrow. 'And if you tell lies, you will be locked up and I'll see to it that there's big trouble for your mother!' Granny nodded. 'He found out about the Ghost, didn't he?' she said. 'The Ghost who comes out when he has a mask on. . . doesn't he, Walter Plinge? And the man thought: I can use that. And when it's time for the Ghost to be caught. . . well, there is a Ghost that can be caught. And the best thing is that everyone will believe it. They'll feel bad about themselves, maybe, but they'll believe it. Even Walter Plinge won't be certain, 'cos his mind's all tangled up.' Granny took a deep breath. 'It's tangled, but it ain't twisted.' There was a sigh. 'Well, matters will have to resolve themselves. There's nothing else for it.' She removed her hat and fished around in the point. 'I don't mind tellin' you this, Walter,' she said, 'because you won't understand and you won't remember. There was a wicked ole witch once called Black Aliss. She was an unholy terror. There's never been one worse or more powerful. Until now. Because I could spit in her eye and steal her teeth, see. Because she didn't know Right from Wrong, so she got all twisted up and that was the end of her. 'The trouble is, you see, that if you do know Right from Wrong you can't choose Wrong. You just can't do it and live. So. . . if I was a bad witch I could make Mister Salzella's muscles turn against his bones and break them where he stood. . . if I was bad. I could do things inside his head, change the shape he thinks he is, and he'd be down on what'd been his knees and begging to be turned into a frog. . . if I was bad. I could leave him with a mind like a scrambled egg, listening to colours and hearing smells. . . if I was bad. Oh, yes.' There was another sigh, deeper and more heartfelt. 'But I can't do none of that stuff: That wouldn't be Right.' She gave a deprecating little chuckle. And if Nanny Ogg had been listening, she would have resolved as follows: that no maddened cackle from Black Aliss of infamous memory, no evil little giggle from some crazed vampyre whose morals were worse than his spelling, no sidesplitting guffaw from the most inventive torturer, was quite so unnerving as a happy little chuckle from a Granny Weatherwax about to do what's best. From the point of her hat Granny withdrew a paper-thin mask. It was a simple face-smooth, white, basic. There were semi-circular holes for the eyes. It was neither happy nor sad. She turned it over in her hands. Walter seemed to stop breathing.

'Simple thing, ain't it?' said Granny. 'Looks beautiful, but it's really just a simple bit of stuff, just like any other mask. Wizards could poke at this for a year and still say there was nothing magic about it, eh? Which just shows how much they know, Walter Plinge. ' She tossed it to him. He caught it hungrily and pulled it over his face. Then he stood up in one flowing movement, moving like a dancer. 'I don't know what you are when you're behind the mask,' said Granny, 'but “ghost” is just another word for “spirit” and “spirit” is just another word for “soul”. Off you go, Walter Plinge.' The masked figure did not move. 'I meant. . . off you go, Ghost. The show must go on.' The mask nodded, and darted away. Granny slapped her hands together like the crack of doom. 'Right! Let's do some good!' she said, to the universe at large. Everyone was looking at her. This was a moment in time, a little point between the past and future, when a second could stretch out and out. . . Agnes felt the blush begin. It was heading for her face like the revenge of the volcano god. When it got there, she knew, it would be all over for her. You'll apologize, Perdita jeered. 'Shut up!' shouted Agnes. She strode forward before the echo had had time to come back from the further ends of the auditorium, and wrenched at the red mask. The entire chorus came in on cue. This was opera, after all. The show had stopped, but opera continued. . . 'Salzella!' He grabbed Agnes, clamping his hand over her mouth. His other hand flew to his belt and drew his sword. It wasn't a stage prop. The blade hissed through the air as he spun to face the chorus. 'Oh dear oh dear oh dear,' he said. 'How extremely operatic of me. And now, I fear, I shall have to take this poor girl hostage. It's the appropriate thing to do, isn't it?' He looked around triumphantly. The audience watched in fascinated silence. 'Isn't anyone going to say “You won't get away with this”?' he said. 'You won't get away with this,' said André, from the wings. 'You have the place surrounded, I have no doubt?' said Salzella brightly. 'Yes, we have the place surrounded.' Christine screamed and fainted. Salzella smiled even more brightly. 'Ah, now there's someone operatic!' he said. 'But, you see, I am going to get away with it, because I don't think operatically. Myself and this young lady here are going to go down to the cellars where I may, possibly, leave her unharmed. I doubt very much that you have the cellars surrounded. Even I don't know everywhere they go, and believe me my knowledge is really rather extensive' He paused. Agnes tried to break free, but his grip tightened around her neck. 'By now,' he said, 'someone should have said: “But why, Salzella?” Honestly, do I have to do everything around here?' Bucket realized he had his mouth open. 'That's what I was going to say!' he said. 'Ah, good. Well, in that case, I should say something like: Because I wanted to. Because I rather like money, you see. But more than that'- he took a deep breath-'I really hate opera. I don't want to get needlessly