You did not have to be a great world traveller to understand that the purpose of this tableau was not to give the chained man a signed testimonial and a collection from everyone at the office.

Granny nudged a bystander.

"What's happening?"

The man looked sideways at her.

"The guards caught him thieving," he said.

"Ah. Well, he looks guilty enough," said Granny. People in chains had a tendency to look guilty. "So what're they going to do to him?"

"Teach him a lesson."

"How d'they do that, then?"

"See the axe?"

Granny's eyes hadn't left it the whole time. But now she let her attention rove over the crowd, picking up scraps of thought.

An ant has an easy mind to read. There's just one stream of big simple thoughts: Carry, Carry, Bite, Get Into The Sandwiches, Carry, Eat. Something like a dog is more complicated - a dog can be thinking several thoughts at the same time. But a human mind is a great sullen lightning-filled cloud of thoughts, all of them occupying a finite amount of brain processing time. Finding whatever the owner thinks they're thinking in the middle of the smog of prejudices, memories, worries, hopes and fears is almost impossible.

But enough people thinking much the same thing can be heard, and Granny Weatherwax was aware of the fear.

"Looks like it'll be a lesson he won't forget in a hurry," she murmured.

"I reckon he'll forget it quite quickly," said the watcher, and then shuffled away from Granny, in the same way that people move away from lightning rods during a thunderstorm.

And at this point Granny picked up the discordant note in the orchestra of thought. In the middle of it were two minds that were not human.

Their shape was as simple, clean and purposeful as a naked blade. She'd felt minds like that before, and had never cherished the experience.

She scanned the crowd and found the minds' owners. They were staring unblinkingly at the figures on the platform.

The watchers were women, or at least currently the same shape as women; taller than she was, slender as sticks, and wearing broad hats with veils that covered their faces. Their dresses shimmered in the sunlight - possibly blue, possibly yellow, possibly green. Possibly patterned. It was impossible to tell. The merest movement changed the colours.

She couldn't make out their faces.

There were witches in Genua all right. One witch, anyway.

A sound from the platform made her turn.

And she knew why people in Genua were quiet and nice.

There were countries in foreign parts, Granny had heard, where they chopped off the hands of thieves so that they wouldn't steal again. And she'd never been happy with that idea.

They didn't do that in Genua. They cut their heads off so they wouldn't think of stealing again.

Granny knew exactly where the witches were in Genua now.

They were in charge.

Magrat reached the house's back door. It was ajar.

She pulled herself together again.

She knocked, in a polite, diffident sort of way.

"Er - " she said.

A bowlful of dirty water hit her full in the face. Through the tidal roaring of a pair of ears full of suds, she heard a voice say, "Gosh, I'm sorry. I didn't know anyone was standing there."

Magrat wiped the water out of her eyes, and tried to focus on the dim figure in front of her. A kind of narrative certainty rose in her mind.

"Is your name Ella?" she said.

"That's right. Who're you?"

Magrat looked her new-found god-daughter up and down. She was the most attractive young woman Magrat had ever seen - skin as brown as a nut, hair so blonde as to be almost white, a combination not totally unusual in such an easygoing city as Genua had once been.

What were you supposed to say at a time like this?

She removed a piece of potato peel from her nose.

"I'm your fairy godmother," she said. "Funny thing, it sounds silly now I come to tell someone - "

Ella peered at her.

"You?"

"Um. Yes. I've got the wand, and everything." Magrat waggled the wand, in case this helped. It didn't.

Ella put her head on one side.

"I thought you people were supposed to appear in a shower of glittering little lights and a twinkly noise," she said suspiciously.

"Look, you just get the wand," said Magrat desperately. "You don't get a whole book of instructions."

Ella gave her another searching look. Then she said, "I suppose you'd better come in, then. You're just in time. I was making a cup of tea, anyway."

The iridescent women got into an open-topped carriage. Beautiful as they were, Granny noted, they walked awkwardly.

Well, they would. They wouldn't be used to legs.

She also noticed the way people didn't look at the carriage. It wasn't that they didn't see it. It was simply that they wouldn't let their gaze dwell on it, as if merely recognizing it would lead them into trouble.

And she noticed the coach horses. They had better senses than the humans did. They knew what was behind them, and they didn't like it at all.

She followed them as they trotted, flat-eared and wild-eyed, through the streets. Eventually they were driven into the driveway of a big and dilapidated house near the palace.

Granny lurked by the wall and noted the details. Plaster was dropping off the house walls, and even the knocker had fallen off the door.

Granny Weatherwax did not believe in atmospheres.

She did not believe in psychic auras. Being a witch, she'd always thought, depended more on what you didn't believe. But she was prepared to believe that there was something very unpleasant in that house. Not evil. The two not-exactly-women weren't evil, in the same way that a dagger or a sheer cliff isn't evil. Being evil means being able to make choices. But the hand wielding a dagger or pushing a body over a cliff could be evil, and something like that was going on.

She really wished that she didn't know who was behind it.

People like Nanny Ogg turn up everywhere. It's as if there's some special morphic generator dedicated to the production of old women who like a laugh and aren't averse to the odd pint, especially of some drink normally sold in very small glasses. You find them all over the place, often in pairs.

They tend to attract one another. Possibly they broadcast inaudible signals indicating that here is someone who could be persuaded to go ‘Ooo' at pictures of other people's grandchildren.

Nanny Ogg had found a friend. Her name was Mrs Pleasant, she was a cook, and she was the first black person Nanny had ever spoken to. She was also a cook of that very superior type who spends most of the time holding court in a chair in the centre of the kitchen, apparently taking very little heed of the activity going on around her.

Occasionally she'd give an order. And they'd only need to be occasionally, because she'd seen to it over the years that people either did things her way or not at all. Once or twice, with some ceremony, she'd get up, taste something, and maybe add a pinch of salt.

Such people are always ready to chat to any wandering pedlars, herbalists, or little old women with cats on their shoulders. Greebo rode on Nanny's shoulder as though he'd just eaten the parrot.

"You be a-comin' here for Fat Lunchtime, then?" said Mrs Pleasant.

"Helping a friend with a bit of business," said Nanny. "My, these biscuits are tasty."

"I means, I see by your eye," said Mrs Pleasant, pushing the plate nearer to her, "that you are of a magical persuasion."

"Then you sees a lot further than most people in these parts," said Nanny. "Y'know, what'd improve these biscuits no end'd be something to dip ‘em in, what d'you think?"

"How "bout something with bananas in it?"

"Bananas would be just the thing," said Nanny happily. Mrs Pleasant waved imperiously at one of the maids, who set to work.