They landed with a thud and Moll blinked into the darkness as the stone above them closed back into place, blocking out the moors. They were in an underground tunnel, lit by candles fixed inside iron brackets, which was several metres wide with earth walls that curved above them into a web of heather roots.

‘Grand,’ Aira said, brushing the soil from Moll’s coat. ‘No broken bones, I hope?’

Gryff picked himself up, then looked down the tunnel in front of them, his hackles raised.

Moll ran a hand over his back. ‘I don’t like being underground either,’ she whispered to him.

‘The feather’s here though, I’m sure of it,’ Aira said. ‘And I’ve coins for any price Kittlerumpit names.’

Gryff growled into the tunnel and Moll could tell that he was still unsure of the place.

‘I’ll go first if your wildcat’s feeling a bit nervous,’ Aira added.

Gryff prowled past her, turning briefly to show his fangs, then stalked on ahead.

‘Don’t take it personally,’ Moll said to Aira. ‘His people skills aren’t much good.’

Aira winked. ‘You’ve got a lot in common, you two.’

Moll tried to smile, but ended up scowling. She walked abreast with Aira. ‘How do you think we find Kittlerumpit?’

Aira shrugged. ‘All I know is that he lives beneath Whuppity Cairns.’ She placed a hand on her crossbow and kept it there. ‘Keep your wits about you, lass. I’m not quite sure what to expect from a trickster goblin.’

Moll remembered how both her arrows had missed the peatbogger earlier and she fumbled inside her coat pocket for her catapult instead – perhaps she’d have more luck with that. But as the dimly lit passageway wound on into the heart of the moor, twisting this way and that, one thing became crystal clear: this was no tunnel. At every juncture there were three or four paths to choose from. It was a maze.

‘Aira,’ Moll said, casting her eyes upwards. ‘We’re back where we started . . .’

Aira cursed as she looked at the slab above them and then Moll had an idea. She dug a hand into her pocket and drew out the piano string. It was almost completely invisible in the tunnel, but now and again the light cast by the candles caught an edge and it glinted gold.

‘This is the last note of the witches’ song,’ Moll said. ‘It’s what Willow told us to find first.’

Aira squinted at it. ‘It’s beautiful, but how’s it going to help us?’

Moll tied the end to the candle bracket on the wall beside her. ‘The string is never-ending, just like the witches’ song was. If we wind out the string as we walk, it’ll show us where we’ve already been.’

Aira’s face lit up. ‘And it’ll show us how to get back too; I don’t much fancy being trapped down here.’

Moll nodded, then, with Gryff by her side, she walked on down the tunnel, threading the piano string out through her fingers. But the further they went, the more on edge Gryff became. He shied at shadows cast by the candles and backed up into Moll when the path forked. Something about the place unsettled him and the same uneasiness whispered inside Moll too. She turned to Aira and, just as she was about to suggest going back towards the cairns, something swung down from the tunnel roof in front of them.

Moll leapt backwards, crashing into Gryff. Hanging upside down from a loose root was the most extraordinary little man Moll had ever seen. For a start, he was green. A round, bald head set above an even rounder pot belly, despite his scrawny arms and legs, made him look like a series of cabbages placed one on top of the other. He wore a tattered waistcoat, undone to reveal his belly, and ripped trousers, but perhaps strangest of all were his ears which were four times the size of ordinary ears, and pointed. He blinked two black eyes at his visitors.

‘Ladies,’ he said, his voice high and reedy. ‘Kittlerumpit, at your service. How kind of you to drop by.’

Aira drew breath to say something, but the goblin’s words filled every space.

‘Safe journey here? Didn’t mind the front door too much? Staying long?’ He stretched out a thin green arm towards them. ‘Allow Kittlerumpit to take your coats.’

Neither Moll nor Aira offered theirs up and Moll found herself gripping tighter on the piano string and feeling suddenly glad that she had trailed it in the shadows so that Kittlerumpit couldn’t see it. Gryff bared his teeth as the goblin flipped his body upright and then dropped down into the tunnel.

‘Come browse, come buy – the place is yours for the looking.’ He strained a gleaming eyeball up against Moll and sniffed. ‘Fresh from the moors, are you? Come for something in particular?’

Moll started to say something, but Aira cut across her. ‘We’d like to browse for now. That’s all.’

The goblin’s gaze lingered on Moll for a moment longer than it needed to, then he clasped his hands in delight and skipped further down the tunnel.

‘This way to Kittlerumpit’s treasures,’ he sang. ‘Come along, come along.’

‘Don’t let on that we need the feather just yet,’ Aira whispered. ‘I don’t trust him one bit.’ She paused. ‘And keep that piano string hidden.’

Moll tucked the reel into her pocket and kept just a single thread between her fingers, unravelling it into the shadows a little more with every step she took. On they went, following the goblin deeper into his lair, and as they rounded a corner into yet another passageway, Moll’s eyes grew large.

Cut into the soiled walls were ledges and shelves, and rammed into every space were dozens of rusted cages, each one holding something different: giant eggs, silver horns, rings carved from bone, golden furs, jewels as large as plates and cloaks made from butterfly wings. And there were wooden boxes hanging down from the roots in the roof laden with unusual treasures: a snowflake the size of Moll’s hand, unmelted and perfectly formed; a slice of rainbow; clocks that read the time backwards and raindrops dancing inside a sealed jar.

Moll ducked beneath the boxes and squinted into the cages, but there was no sign of the burning wings. Aira drew out a purse of gold coins, but, as Kittlerumpit turned his head, he merely giggled.

‘Put that away now,’ he said, closing a cold, clammy hand over Aira’s. ‘Kittlerumpit does things differently down here.’ He turned to Moll and then pointed to the cages and boxes around him. ‘A dragon egg – it’s yours in exchange for your dreams. A slice of rainbow – yours to keep at the cost of your sanity. A unicorn horn – a deal if you’ll hand over your voice.’

Moll flinched at his words. They rolled off Kittlerumpit’s tongue as if he was talking about the weather, but each deal the goblin sought to strike made Moll’s spine tingle. Kittlerumpit stopped suddenly between two cages. In one lay a purse made from dark brown hair and in the other was a yellowy brown necklace.

He chuckled to himself. ‘A wallet made from the nose hair of trolls and a necklace sculpted from imps’ toenails – one day Kittlerumpit will find a bidder.’ His eyes slid down to Gryff and his voice dropped lower. ‘How much for your cat, little girl?’

Moll stood in front of Gryff. ‘He’s not for sale.’

The goblin stamped his foot, then he craned his head round Moll and steepled his fingers. ‘Oh, but his fur . . . what a fine rug it would make for Kittlerumpit’s poor, tired feet as he climbs out of bed each morning.’

Moll spat on the ground in anger and Aira stepped forward to prevent a fight. ‘You heard the girl,’ Aira said. ‘The wildcat’s not for sale.’

The goblin shrugged. ‘Suit yourselves.’ He opened the cage containing the necklace, slipped a hand inside, snapped off a nail and then raised it to his mouth. He chewed for a few seconds before swallowing. ‘Naughty Kittlerumpit,’ he giggled. ‘But sometimes he just can’t help himself.’

Moll tried not to think about how far inside the moors they’d walked with this detestable little goblin and drew herself up tall. Then she glanced at Aira who nodded.

‘We’re after a feather from burning wings,’ Moll said.

Kittlerumpit blinked once, but his face betrayed no emotion. Then, after a pause, he chuckled. ‘This way.’

They followed him down another passageway. There were fewer candles flickering on the walls here and long shadows covered many of the cages, but Moll could see something glowing at the end of the tunnel – not a candle this time, but something larger and brighter. She quickened her step, loosening more and more of the string as she hurried after Kittlerumpit until they came to the cage she’d been searching for. It was bigger than the rest – it had to be – because inside it was an enormous pair of wings with feathers as gold as freshly minted coins.

Moll slotted the string into her pocket, pulled the catch back on the cage and reached inside. But as soon as her fingertips met with the feathers a sharp pain seared through her. She jumped backwards.

Kittlerumpit scowled and closed the cage. ‘Touching a pair of burning wings before you’ve struck a deal with Kittlerumpit – tut-tut . . .’

Moll rubbed her hand and peered through the bars with Gryff and Aira while the goblin drummed his bony fingers against the cage.

‘The feathers of the last phoenix to fly in our world.’ The goblin’s face crumpled into a smile. ‘And one of these feathers will cost you . . .’

Moll leant forward. ‘Yes? How much?’

The goblin closed his eyes for a moment and began counting on his fingers as if he was adding up a complicated sum. Then his eyes sprang open. ‘A feather from the burning wings will cost you a page from your story.’

For a second, Moll thought she’d misheard him. ‘A page from my story? I – I don’t understand . . .’

Gryff sidled up to Moll, turning narrow eyes towards the goblin.

Kittlerumpit began to hop up and down, wringing his hands impatiently. ‘What will it be, girl? A page from your story for the feather you crave? Or will you go home empty-handed?’

Aira shook her head. ‘Be careful, Moll. We don’t know what he means.’

Moll’s mind spun. What Kittlerumpit was saying didn’t make any sense. She didn’t have any books with her. There was nothing to trade. But compared to the other deals she’d heard him muttering about this was nothing. And yet she knew the goblin couldn’t be trusted, and something about his words made Moll’s scalp crawl. She opened her mouth, ready to make her choice, then her eyes flitted to a smaller cage beside the one that held the golden wings. She blinked once, twice, then a third time just to be sure. Her legs wobbled beneath her and she bent down, her hands gripping tightly to the bars. Inside the smaller cage were things she recognised, things she’d been trying to hold dear though their memory was fading.

Here were Alfie’s belongings: his jay feather earring, a lock of his cob’s hair, an owl feather just like the ones that had fletched his arrows and a piece of parchment bearing some of the very last words he’d said to her: ‘I’ll always come after you, Moll.’

‘Go on,’ the goblin said quietly, slipping a wrinkled hand down to open the cage door. ‘You can touch this time.’

Moll picked up the earring and held it in her palm. She squeezed tighter and tighter as if by holding it she might somehow bring Alfie back, then she closed her eyes and tried to imagine that he was by her side. No image appeared in her mind though; it was as if his face was slipping from her grasp.

She turned to Kittlerumpit. ‘Do you have him? Is Alfie here somewhere?’

Aira bent down next to Moll and whispered in her ear. ‘Be careful. Trust your gut – not the illusions the goblin puts in front of you.’

Kittlerumpit glanced at the golden wings. ‘It seems we have a choice.’ He clapped his hands in delight. ‘Kittlerumpit does so love choices. So, what will it be, girl? Your Alfie or your feather? And I’ll keep it simple for you: whichever you choose, it’ll cost you a page from your story.’

Moll shook her head. ‘But . . . Alfie. Is he here?’

The goblin scratched his head. ‘So many cages, so many visitors.’ He sniggered. ‘Kittlerumpit forgets!’

Moll drew herself up. ‘No,’ she said firmly. ‘You don’t forget. You could never forget someone like Alfie. He’s brave and good and – and – even though not everyone can see him you’d never forget him. Not ever.’

Kittlerumpit giggled. ‘Alfie’s belongings are here so maybe he is too. What will you choose: the feather or your friend?’

Gryff pressed up against Moll’s legs and she wished she could find a way into his thoughts. Was Alfie here, somewhere, or was this all a trick? She looked at Aira.

‘What do I do? Willow told me to find the feather, but . . . if Alfie’s here, then I have to go after him! I made a promise!’

‘Go with your gut,’ Aira said again. ‘Even if it’s not what’s easiest.’

Moll looked at Gryff with desperate eyes. She hadn’t asked to be part of the Bone Murmur, to be wrenched from the forest and tasked with beating the Shadowmasks. She thought of what lay ahead: finding the amulet, then destroying the last two witch doctors and the Veil to stop the eternal night. The quest was so big and, faced with the choice now, Moll wanted to give it all up and choose Alfie.

And yet . . . she knew that the old magic was worth fighting for. Willow had told her to go after the feather and she had helped them in the forest when they were lost and in danger, and she had cured Oak’s leg and helped their smuggler friend, Scrap. Moll couldn’t just give up on the old magic, on something her own parents had dedicated their lives to.

‘I – I can’t choose,’ Moll stammered.

Aira placed a hand on Moll’s back. ‘You have to, Moll. I’m here with you, but I can’t tell you what’s right.’ She paused. ‘If you think getting Alfie back will help us destroy the Shadowmasks, then choose him, but we don’t know he’s actually here.’ She lowered her voice. ‘And this goblin is bound up in the witch doctors’ dark magic. Remember that.’

Kittlerumpit’s eyes were black and shining. ‘Oh, we’re all having so much fun, aren’t we?’

Moll looked at the earring in her palm, then at the horse hair and parchment in the cage. They sang of Alfie’s story, but they were just objects, fragments from a time they’d had together, while in the other cage was the next step towards the amulet. Moll closed her eyes again.

This time though she saw Alfie.

He wasn’t a blurred face or a half-remembered figure, as he was in her dreams every night. This was different. She could see him clearly in her mind now and he was smiling, his fair hair flopped down over his eyes, his bow and arrow slung over his shoulder. Moll hardly dared move or breathe as she watched his mouth open a fraction and shape words she felt that she alone could hear. Then the image of Alfie faded and Moll’s eyes sprang open – but his words were still ringing in her ears.

Find the amulet.

And somehow Moll knew in that moment that the feeling in her gut had been right. Alfie was alive and he had found a way to tell her so. She looked at Kittlerumpit and thought of how Alfie had sacrificed himself to destroy the Soul Splinter and she realised that she, too, would choose the old magic because, in finding the amulet, she would find Alfie again.

‘The feather from burning wings,’ Moll said at last. ‘That’s what I choose.’

‘You’re sure?’ the goblin crooned.

Moll blinked, forcing down the tears that were prickling her throat at the thought of being wrong. ‘The feather,’ she said again, placing the earring back in Alfie’s cage.

Kittlerumpit let the door of the larger cage creak open, then he gestured to Moll. ‘Go on then. Take one.’

Hesitantly, Moll stretched out a hand. Her fingertips met with the soft gold feathers but unlike before they didn’t scald her skin when she tugged at the largest one and lifted it out of the cage. It was the size of her arm and it glinted in the candlelight. Moll placed it in her quiver, next to her arrows, and tried not to look back at the rusted cage containing Alfie’s things.

Kittlerumpit stooped towards a ledge and picked up a small yellowed animal skull. Moll noticed that it was filled with water.

‘Now drink to seal our deal,’ he said.

Moll took a step backwards, but Kittlerumpit clamped a bony hand round her wrist. ‘Drink from the raven’s skull or the feather stays here.’

Aira watched nervously as the goblin placed the skull into Moll’s trembling palm, but, as she lowered her lips towards it, Gryff leapt up and tipped the skull towards him, draining the water in a single gulp. The wildcat hissed and then shook his head, but Kittlerumpit only raised one dark eyebrow.

‘Interesting,’ he muttered. ‘Very interesting.’