Granny Weatherwax's knuckles were as white as her dress.

'Esme? What's happening? What are you doing?' said Nanny.

'Trying ... to ... stop . . . the story,' said Granny.

'What's she doing, then?'

'Letting . . . things . . . happen!'

The crowd were pulling back past them. It didn't seem to be a conscious thing. It was just happening that a sort of corridor was forming.

The Prince walked slowly along it. Behind Lily, faint images hung in the air so that she appeared to be followed by a succession of fading ghosts.

Magrat stood up.

Nanny was aware of a rainbow hue in the air. Possibly there was the tweeting of bluebirds.

The Prince took Magrat by the hand.

Nanny glanced up at Lily Weatherwax, who had remained a few steps up from the foot of the stairs and was smiling beneficently.

Then she tried to put a focus on the future.

It was horribly easy.

Normally the future is branching off at every turn and it's only possible to have the haziest idea of what is likely to happen, even when you're as temporally sensitive as a witch. But here there were stories coiled around the tree of events, bending it into a new shape.

Granny Weatherwax wouldn't know what a pattern of quantum inevitability was if she found it eating her dinner. If you mentioned the words 'paradigms of space-time' to her she'd just say 'What?' But that didn't mean she was ignorant. It just meant that she didn't have any truck with words, especially gibberish. She just knew that there were certain things that happened continually in human history, like three-dimensional cliches. Stories.

'And now we're part of it! And I can't stop it,' said Granny. 'There's got to be a place where I can stop it, and I can't find it!'

The band struck up. It was playing a waltz.

Magrat and the Prince whirled around the dance floor once, never taking their eyes off each other. Then a few couples dared to join them. And then, as if the whole ball was a machine whose spring had been wound up again, the floor was full of dancing couples and the sounds of conversation flowed back into the void.

'Are you going to introduce me to your friend?' said Casanunda, from somewhere near Nanny's elbow. People swept past them.

'It's all got to happen,' said Granny, ignoring the low-level interruption. 'Everything. The kiss, the clock striking midnight, her running out and losing the glass slipper, everything.'

'Ur, yuk,' said Nanny, leaning on her partner's head. Td rather lick toads.'

'She looks just my type,' said Casanunda, his voice slightly muffled. 'I've always been very attracted to dominant women.'

The witches looked at the whirling couple, who were staring into one another's eyes.

'I could trip them up, no trouble,' said Nanny.

'You can't. That's not something that can happen.'

'Well, Magrat's sensible . . . more or less sensible,' said Nanny. 'Maybe she'll notice something's wrong.'

'I'm good at what I do, Gytha Ogg,' said Granny. 'She won't notice nothing until the clock strikes midnight.'

They both turned to look up. It was barely nine.

'Y'know,' said Nanny Ogg. 'Clocks don't strike midnight. Seems to me they just strike twelve. I mean, it's just a matter of bongs.'

They both looked up at the clock again.

In the swamp, Legba the black cockerel crowed. He always crowed at sunset.

Nanny Ogg pounded up another flight of stairs and leaned against the wall to catch her breath.

It had to be somewhere round here.

'Another time you'll learn to keep your mouth shut, Gytha Ogg,' she muttered.

'I expect we're leaving the hurly-burly of the ball for an intimate tete-a-tete somewhere?' said Casanunda hopefully, trotting along behind her.

Nanny tried to ignore him and ran along a dusty passage. There was a balcony rail on one side, looking down into the ballroom. And there . . .

... a small wooden door.

She rammed it open with her elbow. Within, mechanisms whirred in counterpoint to the dancing figures below as if the clock was propelling them, which, in a metaphorical sense, it was.

Clockwork, Nanny thought. Once you know about clockwork, you know about everything.

I wish I bloody well knew about clockwork.

'Very cosy,' said Casanunda.

She squeezed through the gap and into the clock space. Cog-wheels clicked past her nose.

She stared at them for a moment.

Lawks. All this just to chop Time up into little bits.

'It might be just the teensiest bit cramped,' said Casanunda, from somewhere near her armpit. 'But needs must, ma'am. I remember once in Quirm, there was this sedan chair and . . .'

Let's see, thought Nanny. This bit is connected to that bit, this one turns, that one turns faster, this spiky bit wobbles backwards and forwards . . .

Oh, well. Just twist the first thing you can grab, as the High Priest said to the vestal virgin.*

Nanny Ogg spat on her hands, gripped the largest cogwheel, and twisted.

It carried on turning, pulling her with it.

Blimey. Oh, well . . .

Then she did what neither Granny Weatherwax nor Magrat would have dreamed of doing in the circumstances. But Nanny Ogg's voyages on the sea of inter-sexual dalliance had gone rather further than twice around the lighthouse, and she saw nothing demeaning in getting a man to help her.

She simpered at Casanunda.

'Things would be a lot more comfortable in our little pie-de-terre if you could just push this little wheel around a bit,' she said. 'I'm sure you could manage it,' she added.

'Oh, no problejn, good lady,' said Casanunda. He reached up with one hand. Dwarfs are immensely strong for their size. The wheel seemed to offer him no resistance at all.

Somewhere in the mechanism something resisted for a

* This is the last line of a Discworld joke lost, alas, to posterity.

moment and then went clonk. Big wheels turned reluctantly. Little wheels screamed on their axles. A small important piece flew out and pinged off Casanunda's small bullet head.

And, much faster than nature had ever intended, the hands sped round the face.

A new noise right overhead made Nanny Ogg look up.

Her self-satisfied expression faded. The hammer that struck the hours was swinging slowly backwards. It struck Nanny that she was standing right under the bell at the same time as the bell, too, was struck.

Bong . . .

'Oh, bugger!'

Mist rolled through the swamp. And shadows moved with it, their shapes indistinct on this night when the difference between the living and the dead was only a matter of time.

Mrs Gogol could feel them among the trees. The homeless. The hungry. The silent people. Those forsaken by men and gods. The people of the mists and the mud, whose only strength was somewhere on the other side of weakness, whose beliefs were as rickety and homemade as their homes. And the people from the city — not the ones who lived in the big white houses and went to balls in fine coaches, but the other ones. They were the ones that stories are never about. Stories are not, on the whole, interested in swineherds who remain swineherds and poor and humble shoe-makers whose destiny is to die slightly poorer and much humbler.

These people were the ones who made the magical kingdom work, who cooked its meals and swept its floors and carted its night soil and were its faces in the crowd and whose wishes and dreams, undemanding as they were, were of no consequence. The invisibles.

And me out here, she thought. Building traps for gods.

There are various forms of voodoo in the multiverse, because it's a religion that can be put together from any ingredients that happen to be lying around. And all of them try, in some way, to call down a god into the body of a human being.

That was stupid, Mrs Gogol thought. That was dangerous.

Mrs Gogol's voodoo worked the other way about. What was a god? A focus of belief. If people believed, a god began to grow. Feebly at first, but if the swamp taught anything, it taught patience. Anything could be the focus of a god. A handful of feathers with a red ribbon around them, a hat and coat on a couple of sticks . . . anything. Because when all people had was practically nothing, then anything could be almost everything. And then you fed it, and lulled it, like a goose heading for pate, and let the power grow very slowly, and when the time was ripe you opened the path . . . backwards. A human could ride the god, rather than the other way around. There would be a price to pay later, but there always was. In Mrs Gogol's experience, everyone ended up dying.

She took a pull of rum and handed the jug to Saturday.

Saturday took a mouthful, and passed the jug up to something that might have been a hand.

'Let it begin,' said Mrs Gogol.

The dead man picked up three small drums and began to beat out a rhythm, heartbeat fast.

After a while something tapped Mrs Gogol on the shoulder and handed her the jug. It was empty.

Might as well begin . . .

'Lady Bon Anna smile on me. Mister Safe Way protect me. Stride Wide Man guide me. Hotaloga Andrews catch me.

'I stand between the light and the dark, but that no matter, because I am between.

'Here is rum for you. Tobacco for you. Food for you. A home for you.

'Now you listen to me good . . .'

For Magrat it was like waking from a dream into a dream. She'd been idly dreaming that she was dancing with the most handsome man in the room, and . . . she was dancing with the most handsome man in the room.

Except that he wore two circles of smoked glass over his eyes.

Although Magrat was soft-hearted, a compulsive daydreamer and, as Granny Weatherwax put it, a wet hen, she wouldn't be a witch if she didn't have certain instincts and the sense to trust them. She reached up and, before his hands could move, tweaked the things away.

Magrat had seen eyes like that before, but never on something walking upright.

Her feet, which a moment before had been moving gracefully across the floor, tripped over themselves.

'Er . . .' she began.

And she was aware that his hands, pink and well-manicured, were also cold and damp.

Magrat turned and ran, knocking the couples aside in her madness to get away. Her legs tangled in the dress. The stupid shoes skittered on the floor.

A couple of footmen blocked the stairs to the hall.

Magrat's eyes narrowed. Getting out was what mattered.

'Hai!'

'Ouch!'

And then she ran on, slipping at the top of the stairs. A glass slipper slithered across the marble.

'How the hell's anyone supposed to move in these things?' she screamed at the world in general. Hopping frantically on one foot, she wrenched the other shoe off and ran into the night.

The Prince walked slowly to the top of the steps and picked up the discarded slipper.

He held it. The light glittered off its facets.

Granny Weatherwax leaned against the wall in the shadows. All stories had a turning point, and it had to be close.

She was good at getting into other people's minds, but now she had to get into hers. She concentrated. Down deeper . . . past everyday thoughts and minor concerns, faster, faster . . . through layers of deep cogitation . . . deeper . . . past things sealed off and crusted over, old guilts and congealed regrets, but there was no time for them now . . . down . . . and there . . . the silver thread of the story. She'd been part of it, was part of it, so it had to be a part of her.

It poured past. She reached out.

She hated everything that predestined people, that fooled them, that made them slightly less than human.

The story whipped along like a steel hawser. She gripped it.

Her eyes opened in shock. Then she stepped forward.