Despite the heat, she was dressed in a long black coat that swirled about her like the fog that was creeping into the room. In one hand, she held the silver knife. In the other, a skinny broom. Garstigan sat on her shoulder, leering at the fallen coffin creepers. He was still wearing the yellow doll-hair, Archie noticed.

‘If that’s your Unquiet Night costume, it’s very authentic,’ said Billy. ‘Eight out of ten on the Macabre Creepy Scale.’

‘I prefer the traditional look, at times like this,’ said Mrs Puddingham-Pye, with a smile that was almost warm. ‘I just saved your lives, by the way.’

‘Thank you,’ Archie said, and he meant it. He’d been more scared than he realised. ‘How did you know we’d be here?’

‘I sensed the Taciturnitas Hex had been lifted,’ she said, tucking the knife into her belt. ‘Presumably when Preen was … deactivated.’ She cast a glance at the wooden ex-dentist, crumpled on the floor.

‘Then Garstigan spied the boxy men in the street,’ hissed the mobgoblin, fussily plumping his ringlets. ‘Told his mistress, and we followed their clumpy footsteps. So noisy!’

‘The coffin creepers are wood golems,’ his keeper finished. ‘They’re enchanted by a simple spell and easy to neutralise. All you need to do to is strike through the name on the lid and they don’t know who to chase.’

‘Or you can use your own personal magical flamethrower,’ said Fliss, smugly patting Blossom’s head.

‘A tactic of which my own dear daughter would approve.’

‘Does this mean you’re helping us?’ said Archie.

‘As I said before, Urchin, we’ve a common enemy. I’ve no wish to see the end of magic in Dundoodle any more than you. So, yes, we have a temporary truce. But if you were in possession of your wyrdworking powers, you wouldn’t need my help.’

‘What do you mean?’

‘For example, just like Preen, these coffin creatures were made from timber taken from trees of the old forest, enchanted trees. The same enchantment is at the root of your powers. Your powers come from the forest itself – you could easily have commanded the golems to stop, if you’d known how.’

‘That would have saved us a lot of trouble,’ said Billy.

‘I don’t have time for lessons, right now,’ said Archie. ‘Or any more talking. We need to get to the Wyrdie Tree. The Mirk is on its way to destroy it. And I may not be able to wyrdwork, but I’ve got to do something!’

‘I said the coffins were yours to command,’ Mrs Puddingham-Pye impatiently. ‘Make use of them, boy!’

‘We’ve already got a boat to get us across the loch,’ said Billy.

‘I don’t mean anything so dull.’ The woman marched over to one of the coffins, and stepped into it. She rapped the handle end of her broom on to the floor of the wooden box. Blue lightning rippled down the broom and the coffin rose off the ground, hovering steadily.

‘You, Bilbo!’ barked Mrs Puddingham-Pye, pointing at Billy. ‘Get in!’

He was too stunned to argue. He scrambled inside the coffin and sat down, nervously.

‘Now, boy,’ said the woman, looking at Archie. ‘It’s your turn. The coffin is your servant. Command it, make it do your bidding. Order it to fly.’

Archie felt confused. He didn’t like the idea of commanding anything. He wasn’t like Mrs Puddingham-Pye. Her way wasn’t his way.

‘Do it now, boy!’ the woman snapped. ‘There isn’t any time to lose!’

Archie stepped into the other coffin. He touched its chiselled sides gently, remembering how the tree stumps had felt when they had found them in the old forest, the painful sense of destruction he’d experienced. It was time for this wood to return to the place where it had grown from a seed, and lived for so many years, before it was cut and cruelly manipulated by the Mirk. He felt the coffin’s surface grow warm. A breeze blew through the town, sweeping in through the door, and the fog retreated. The air suddenly began to cool, and as it did the smell of fir trees, birch and oaks, bracken, heather and cool streams swirled around him – the same scent of the forest which he had smelled the day he met the Wyrdie Tree. He felt its strength flow through him.

‘Let’s go,’ he said softly. The coffin wobbled, then lifted shakily off the floor.

‘You’re doing it!’ squealed Fliss, ‘Archie, you’re doing it!’ She jumped into the coffin and sat down. Sherbet dived in after her and sat himself in her lap.

‘Good, boy!’ snarled Mrs Puddingham-Pye. ‘Think of the destination – focus on it in your mind.’

The coffins sailed out of the shop and climbed above the alleyway, Billy and Fliss hanging on to their sides for dear life. The fog was now being scoured from the town, as cooler air swept across the loch and pushed the unpleasant heat away. It was as if nature were joining them in the battle against the Mirk. Archie had to concentrate to keep the coffin airborne in the breeze, and not tip them out over the rooftops, but after a couple of wobbly moments he began to feel more confident. Mrs Puddingham-Pye stood regally as the wind rippled around her, her black coat flying out behind like a raven’s tail.

‘Onward, boy!’ she yelled across to Archie. ‘Onward!’

‘If she had a whip,’ muttered Fliss, ‘she would be cracking it. I reckon you’ve got the hang of your magical powers.’

‘I think they’ve got the hang of me,’ said Archie. ‘It’s like they’re a pair of shoes that have put themselves on my feet and after a few days of hobbling around, finally they’re starting to fit.’

The strange flying-craft sped out over the loch. The low sun poured orange light across it, turning the water the colour of fire.

‘We need to go to Pookiecrag Island,’ Archie called. ‘Jings said the honey dragons would help us!’

Mrs Puddingham-Pye nodded, and the coffins steered towards the ruins of the castle. As they approached, gliding over the tumbledown turrets, they could see something was wrong.

‘What’s that plant growing everywhere?’ said Billy, leaning dangerously over the top of the coffin, making it wobble so much that Mrs Puddingham-Pye had to poke him with her broomstick. ‘It wasn’t there before. And I have to say it’s more Creeping Beauty than Sleeping Beauty.’

The whole castle was covered in a black, prickly vine that had wrapped itself tightly around the stonework.

‘Is it Mirkthorn?’ said Archie, jumping out of the coffin as it landed in the centre of the ruins. ‘Careful of these spikes, they look deadly!’

‘It’s not a plant,’ said Billy. ‘It’s metal. A net of barbed wire.’

The web-like net appeared to spread out from a single point: the fireplace that hid the tunnel to the Cavern of Honeystone. Blossom flew to the fireplace and vainly tried to burn the metal away.

‘This isn’t just the Mirk’s handiwork,’ said Fliss miserably. ‘It had help.’ She pointed to a black wooden star that was fixed to the trapdoor in the hearth. The web had grown from its points, spreading outwards over the castle, and sealing the trapdoor with its stranglehold. There was no way to get the door open – the dragons were trapped!