'It's the mist! Can't you hear it sizzling?'

'A sizzling mist, is it?' The landlord looked at the wall, which was quite empty and unmysterious except for a few cobwebs. The urgency in Mort's voice unsettled him. He would have preferred the normal scaly monsters. A man knew where he stood with them.

'It's coming right across the room! Can't you feel it?'

The customers looked at one another. Mort was making them uneasy. One or two of them admitted later that they did feel something, rather like an icy tingle, but it could have been indigestion.

Mort backed away, and then gripped the bar. He shivered for a moment.

'Look,' said the landlord, 'a joke's a joke, but —'

'You had a green shirt on before!'

The landlord looked down. There was an edge of terror in his voice.

'Before what?' he quavered. To his astonishment, and before his hand could complete its surreptitious journey towards the blackthorn stick, Mort lunged across the bar and grabbed him by the apron.

'You've got a green shirt, haven't you?' he said. 'I saw it, it had little yellow buttons!'

'Well, yes. I've got two shirts.' The landlord tried to draw himself up a little. 'I'm a man of means,' he added. 'I just didn't wear it today.' He didn't want to know how Mort knew about the buttons.

Mort let him go and spun round.

'They're all sitting in different places! Where's the man who was sitting by the fire? It's all changed!'

He ran out through the door and there was a muffled cry from outside. He dashed back, wild-eyed, and confronted the horrified crowd.

'Who changed the sign? Someone changed the sign!'

The landlord nervously ran his tongue across his lips.

'After the old king died, you mean?' he said.

Mort's look chilled him, the boy's eyes were two black pools of terror.

'It's the name I mean!'

'We've – it's always been the same name,' said the man, looking desperately at his customers for support. 'Isn't that so, lads? The Duke's Head.'

There was a murmured chorus of agreement.

Mort stared at everyone, visibly shaking. Then he turned and ran outside again.

The listeners heard hoof beats in the yard, which grew fainter and then disappeared entirely, just as though a horse had left the face of the earth.

There was no sound inside the inn. Men tried to avoid one another's gaze. No-one wanted to be the first to admit to seeing what he thought he had just seen.

So it was left to the landlord to walk unsteadily across the room and reach out and run his fingers across the familiar, reassuring wooden surface of the door. It was solid, unbroken, everything a door should be.

Everyone had seen Mort run through it three times. He just hadn't opened it.

Binky fought for height, rising nearly vertically with his hooves thrashing the air and his breath curling away behind him like a vapour trail. Mort hung on with knees and hands and mostly with willpower, his face buried in the horse's mane. He didn't look down until the air around him was freezing and thin as workhouse gravy.

Overhead the Hub Lights flickered silently across the winter sky. Below —

— an upturned saucer, miles across, silvery in the starlight. He could see lights through it. Clouds were drifting through it.

No. He watched carefully. Clouds were certainly drifting into it, and there were clouds in it, but the clouds inside were wispier and moving in a slightly different direction and, in fact, didn't seem to have much to do with the clouds outside. There was something else . . . oh yes, the Hub Lights. They gave the night outside the ghostly hemisphere a faint green tint, but there was no sign of it under the dome.

It was like looking into a piece of another world, almost identical, that had been grafted on to the Disc. The weather was slightly different in there, and the Lights weren't on display tonight.

And the Disc was resenting it, and surrounding it, and pushing it back into non-existence. Mort couldn't see it growing smaller from up here, but in his mind's ear he could hear the locust sizzle of the thing as it ground across the land, changing things back to where they should be. Reality was healing itself.

Mort knew, without even having to think about it, who was at the centre of the dome. It was obvious even from here that it was centred firmly on Sto Lat.

He tried not to think what would happen when the dome had shrunk to the size of the room, and then the size of a person, and then the size of an egg. He failed.

Logic would have told Mort that here was his salvation. In a day or two the problem would solve itself; the books in the library would be right again; the world would have sprung back into shape like an elastic bandage. Logic would have told him that interfering with the process a second time around would only make things worse. Logic would have said all that, if only Logic hadn't taken the night off too.

Light travels quite slowly on the Disc, due to the braking effect of the huge magical field, and currently that part of the Rim carrying the island of Krull was directly under the little sun's orbit and it was, therefore, still early evening. It was also quite warm, since the Rim picks up more heat and enjoys a gentle maritime climate.

In fact Krull, with a large part of what for want of a better word must be called its coastline sticking out over the Edge, was a fortunate island. The only native Krullians who did not appreciate this were those who didn't look where they were going or who walked in their sleep and, because of natural selection, there weren't very many of them any more. All societies have their share of dropouts, but on Krull they never had a chance to drop back in again.

Terpsic Mims was not a dropout. He was an angler. There is a difference; angling is more expensive. But Terpsic was happy. He was watching a feather on a cork bob gently on the gentle, reed-lined waters of the Hakrull river and his mind was very nearly a blank. The only thing that could have disturbed his mood was actually catching a fish, because catching fish was the one thing about angling that he really dreaded. They were cold and slimy and panicky and got on his nerves, and Terpsic's nerves weren't very good.

So long as he caught nothing Terpsic Mims was one of the Disc's happiest anglers, because the Hakrull river was five miles from his home and therefore five miles from Mrs Gwladys Mims, with whom he had enjoyed six happy months of married life. That had been some twenty years previously.

Terpsic did not pay undue heed when another angler took up station further along the bank. Of course, some fishermen might have objected to this breach of etiquette, but in Terpsic's book anything that reduced his chance of actually catching any of the damned things was all right by him. Out of the corner of his eye he noted that the newcomer was fly-fishing, an interesting pastime which Terpsic had rejected because one spent altogether far too much time at home making the equipment.

He had never seen fly-fishing like this before. There were wet flies, and there were dry flies, but this fly augured into the water with a saw-toothed whine and dragged the fish out backwards.

Terpsic watched in horrified fascination as the indistinct figure behind the willow trees cast and cast again. The water boiled as the river's entire piscine population fought to get out of the way of the buzzing terror and, unfortunately, a large and maddened pike took Terpsic's hook out of sheer confusion.

One moment he was standing on the bank, and the next he was in a green, clanging gloom, bubbling his breath away and watching his life flash before his eyes and, even in the moment of drowning, dreading the thought of watching the bit between the day of his wedding and the present. It occurred to him that Gwladys would soon be a widow, which cheered him up a little bit. In fact Terpsic had always tried to look on the bright side, and it struck him, as he sank gratefully into the silt, that from this point on his whole life could only improve. . . .

And a hand grabbed his hair and dragged him to the surface, which was suddenly full of pain. Ghastly blue and black blotches swam in front of his eyes. His lungs were on fire. His throat was a pipe of agony.

Hands – cold hands, freezing hands, hands that felt like a glove full of dice – towed him through the water and threw him down on to the bank where, after some game attempts to get on with drowning, he was eventually bullied back into what passed for his life.

Terpsic didn't often get angry, because Gwladys didn't hold with it. But he felt cheated. He'd been born without being consulted, he'd been married because Gwladys and her father had seen to it, and the only major human achievement that was uniquely his had been rudely snatched away from him. A few seconds ago it had all been so simple. Now it was all complicated again.

Not that he wanted to die, of course. The gods were very firm on the subject of suicide. He just hadn't wanted to be rescued.

Through red eyes in a mask of slime and duckweed he peered at the blurred form above him, and shouted, 'Why did you have to save me?'

The answer worried him. He thought about it as he squelched all the way home. It sat at the back of his mind while Gwladys complained about the state of his clothes. It squirrelled around in his head as he sat and sneezed guiltily by the fire, because being ill was another thing Gwladys didn't hold with. As he lay shivering in bed it settled in his dreams like an iceberg. In the midst of his fever he muttered, 'What did he mean, “FOR LATER”?'

Torches flared in the city of Sto Lat. Whole squads of men were charged with the task of constantly renewing them. The streets glowed. The sizzling flames pushed back shadows that had been blamelessly minding their own business every night for centuries. They illuminated ancient corners where the eyes of bewildered rats glittered in the depths of their holes. They forced burglars to stay indoors. They glowed on the night mists, forming a nimbus of yellow light that blotted out the cold high flames streaming from the Hub. But mainly they shone on the face of Princess Keli.

It was everywhere. It plastered every flat surface. Binky cantered along the glowing streets between Princess Keli on doors, walls and gable ends. Mort gaped at posters of his beloved on every surface where workmen had been able to make paste stick.

Even stranger, no-one seemed to be paying them much attention. While Sto Lat's night life was not as colourful and full of incident as that of Ankh-Morpork, in the same way that a wastepaper basket cannot compete with a municipal tip, the streets were nevertheless a-bustle with people and shrill with the cries of hucksters, gamblers, sellers of sweetmeats, pea-and-thimble men, ladies of assignation, pickpockets and the occasional honest trader who had wandered in by mistake and couldn't now raise enough money to leave. As Mort rode through them snatches of conversation in half-a-dozen languages floated into his ears; with numb acceptance he realised he could understand every one of them.

He eventually dismounted and led the horse along Wall Street, searching in vain for Cutwell's house. He found it only because a lump on the nearest poster was making muffled swearing noises.

He reached out gingerly and pulled aside a strip of paper.

Tanks very much,' said the gargoyle doorknocker. 'You wouldn't credit it, would you? One minute life as normal, nexft minute a mouthful of glue.'

'Where's Cutwell?'

'He's gone off to the palace.' The knocker leered at him and winked a cast-iron eye. 'Some men came and took all his fstuff away. Then some ovver men started pasting pictures of his girlfriend all over the place. Barftuds,' it added.

Mort coloured.

'His girlfriend?'

The doorknocker, being of the demonic persuasion, sniggered at his tone. It sounded like fingernails being dragged over a file.