The Ice Queen stood up from the organ. ‘Not possible,’ she murmured.

Balapan dived low and landed on Eska’s shoulder and, with the strength of the eagle willing her on, Eska advanced through the hall.

The Ice Queen turned to Slither. ‘Find the boy, just in case he’s lurking – and kill him – while I destroy the eagle.’

The Fur and Feather battle cries clamoured again and Eska, holding the Frost Horn in front of her like a shield, strode on towards the Ice Queen. She had no voice, but she had an eagle on her shoulder and a heart full of courage so she kept walking, veering round the organ to the heap of shattered ice where Blu and Pebble had once been.

‘Soon the ice will melt!’ the queen cried. ‘You’ve lost your friends for ever!’

But Eska wasn’t listening. She raised the Frost Horn to her lips and thought of Blu and Pebble – of the little girl who had left her home to follow her brother through every possible danger and the fox pup who had tried his hardest to protect her in the bay. She blew gently this time and the horn sung a different note again – not the Sky Song or the battle summoning – instead the sound was like clouds rippling, and it stirred the crystals on the floor, whisking them up into the air until they swirled and glimmered.

The Ice Queen rushed forward, but a shape was already emerging within the crystals. Only it wasn’t a statue any more. In its place stood a girl with ruddy cheeks and a bundle of fur wriggling in her arms.

The Ice Queen raised her staff and shrieked. ‘You will not undo my power, Eska!’

Black sparks shot out from her staff, but Eska stood in front of Blu and as she held the Frost Horn in front of her the sparks bounced off and fizzled out on the floor.

‘We Eska’s tribe!’ Blu shouted, no longer scared now that Eska was there to guard her. She stroked Pebble’s head. ‘We her friends and we never give up!’

Balapan cried out from Eska’s shoulder and the Ice Queen stalked closer. ‘Except Flint,’ she said quietly. ‘He seemed very happy to run away earlier.’

Blu shook her head. ‘Flint fight for Eska. Always looking for her. Always fighting for her. Never leave.’

The Ice Queen sighed. ‘Blind as well as stupid . . .’

There was a scuffle of footsteps from the door.

‘Come, Slither!’ the Ice Queen called.

But it was not the shaman who emerged from the passageway.

It was Flint.

The Ice Queen snorted. ‘If you tied Slither up with willow-snatch, he’ll break its curse in an instant.’

Flint raised an eyebrow. ‘Not if the willow-snatch is drenched in water gathered from a whirlpool. That’ll bind him for months on end.’ He paused. ‘You didn’t think I’d enter your palace without a few inventions up my sleeve, did you?’

Eyes wild, the Ice Queen raised her staff towards Flint, but at that moment Blu rushed forward and kicked the queen in the back of the legs.

Flint’s jaw dropped. His sister. Alive and full of fight!

Black sparks ricocheted off the walls as the Ice Queen stumbled to her knees, but it gave Flint the chance he needed and he darted towards the trees, grabbing Blu by the hand as he raced past. He thrust a small wooden box at Eska and from her shoulder Balapan croaked.

‘Your memories,’ Flint panted as Pebble nuzzled round his legs. ‘I searched the whole palace until I found this in the throne turret.’

Eska could scarcely believe what she was hearing. Flint hadn’t abandoned her. He’d gone to find her past.

‘When I saw the Ice Queen’s power over Blu,’ Flint cried, ‘I realised we needed all the help we could get to beat her! You need to remember who you are, Eska, if you’re going to take back your voice.’

The Ice Queen was on her feet again, her staff aimed at Eska. ‘You won’t be able to open it!’ she shrieked. ‘There is no key! I hurled it to the bottom of the ocean the day I captured you!’

Eska’s skin trembled, but Flint held up his Anything Knife to the keyhole and twisted it this way and that.

The Ice Queen strode forward and, though the power of the Frost Horn was enough to keep the black sparks of her magic away from the group, a trail of sweat inched down Eska’s back as Flint worked his knife in the lock.

‘Come on, brother,’ Blu urged. ‘Quick!’

Flint fumbled with the knife, but the Ice Queen was upon them now, brandishing her staff, and then, just as she brought it down, a shadow fell across her. Eska glanced up to see a large shape had filled one of the palace arches and she realised she recognised those broad shoulders and wide-set legs.

Whitefur.

The Erkenbear leapt into the room and bounded across the floor towards the Ice Queen. She took a few steps backwards and then remembered herself and aimed her staff at the raging bear. A burst of sparks shot out and the Erkenbear tumbled backwards, but it was up again in seconds. Flint worked harder with his knife until there was a click and, as Whitefur launched himself at the Ice Queen, Eska pushed the wooden lid open.

A swirl of colours twisted towards her and as they fell about her face it felt, to Eska, as if she was looking at a rainbow through the mist. But then the mist seemed to fade and the colours became stronger and, finally, Eska saw her past clearly. She was sledging in the Never Cliffs with her ma, then she was hunting caribou on the Driftlands with her pa. Next she was making necklaces from river quartz with her parents, then she was running, hand in hand with them, across the foothills to catch a glimpse of a golden eagle.

This was her past. A lifetime out in the wild with two people who loved her more than she could have hoped for. And suddenly knowing her place, knowing her beginnings and all that had come after that, made her grip the Frost Horn harder.

Whitefur wrestled with the Ice Queen, a whirl of claws and nails and fizzing black sparks, and as Eska saw them like that a more painful memory surfaced: the last moments with her parents on the Driftlands. Her ma crying out for her as the wolverines closed in, the Erkenbear trying to set things right and then a Tusk warrior dragging her and her pa to Winterfang.

Whitefur hadn’t managed to hold the Ice Queen back then, but now he fought with a vengeance and, as he thumped an enormous paw across the queen’s chest, pinning her to the ground, he growled at Eska. And Eska could hear the words in that growl because it was the language of those who wandered the wild.

Take what it rightfully yours, it said. Take back your voice.

Eska stormed towards the Ice Queen while Flint shoved Blu behind him and took on the stream of Tusk guards pouring through the arches. Whitefur winced as the Ice Queen struggled beneath him and sent a fresh flurry of sparks into his side, but Eska was running now and she swung the Frost Horn at the Ice Queen’s staff. The sceptre broke apart upon impact, shattering into fragments of black ice.

The queen gasped as the ice melted before her eyes and a gold mist seeped from her lips. It drifted into the hall and settled inside the baubles on the trees until all of them shone gold once again. The Ice Queen raised a hand to her mouth, but an even brighter mist was slipping through her fingers now – a mist that burned as gold as Balapan’s eyes. It swirled into the hall and Eska stood, completely still, as she breathed her voice back inside her.

Leaving Flint to fight the last of the Tusk guards, Eska sped across the room and leapt up into an open arch. Balapan glided to her shoulder and they looked at the fight below, a frenzy of blizzard balls, ice spears and willow-snatching javelins. Then Eska held the Frost Horn high and, desperately hoping she could remember its song, she threw her newfound voice out into the night.

At first she sang the low, clear note – the one that had sounded like an owl’s hoot – then she launched into the rippling melody and her song rose like bubbles from the depths of the sea.

A few of the Tusk guards looked up at her, their weapons suddenly limp in their hands, and Eska noticed then that their expressions had changed. They were no longer blank and ice-eyed; their faces were filled with shock and shame and something like hope and, though Eska didn’t dare stop singing, she wondered whether the Ice Queen’s hold over her Tusk army was gradually weakening.

Eska let the melody grow louder, stronger, and, as the Sky Song burst out, she could feel the power of the mountains and the forests and the glaciers stirring inside her.

More Tusk guards stopped fighting, the wolverines and the Erkenbears broke apart, and Eska saw Rook, her face brighter and kinder than it had been in the Lost Chambers, push her way through the crowds towards the palace until she was standing alongside Jay and Tomkin. Eska blinked. Even the Tusk guards frozen by blizzard balls and imprisoned by willow-snatch were breaking free from the magic that had bound them and looking up to her with eager faces. All the tribes were listening now. Because the Ice Queen’s curses had worn off.

Eska raised her eyes to the stars, to the mighty Sky Gods glistening from above, and as she sang the last part of the Sky Song – the melody filled with longing and heart and infinite wonder – the sound of her voice swirled up into the night and the northern lights began to dance.

Balapan leapt from her shoulder, wheeling into the colours that spilled into rings and halos across the dark, and Eska knew then that no one in Erkenwald could doubt the presence of magic. The Sky Gods were up there and they were dancing for every tribe to see.

Eska cleared her throat. ‘A few weeks ago, I was nothing more than a prisoner here at Winterfang!’ she cried. ‘The Ice Queen locked me in a music box and told me I was cursed! She stole my parents, she stole my memories and then she stole my voice.’ Eska took a deep breath. ‘But, together with the bravest inventor I know, I escaped and formed a tribe. And, though it wasn’t made up of warriors or people who dressed and thought the same way, it was enough. Because we were brave and we kept hoping, and though the Ice Queen threw everything she had at us – Tusk guards, cursed wolves, mountain ghouls and thunderghosts – we threw more back.’

Balapan settled on her shoulder and ruffled her feathers. ‘We kept going when everything fell apart! We trusted strangers even when we didn’t have a plan!’ She paused. ‘And when the Ice Queen tried to silence us we shouted louder!’ She raised the Frost Horn high. ‘For almost a year, we’ve lived in a kingdom shrunk to whispers, in a place where the tribes hide from one another in fear, but that is not our Erkenwald! It’s time to reclaim our kingdom!’

There was a deafening roar from below as all three tribes cheered Eska on. She spun round to see the last of the Tusk guards sitting on the floor, shaking his head as if waking from a terrible dream, and she knew that the Ice Queen’s curse had been broken once and for all.

She watched as Flint raked his Anything Knife through the baubles that hung from the trees. They crashed to the ground, finally free from the Ice Queen’s enchantment, and as Blu stamped them into tiny pieces, the golden glow of the imprisoned voices drifted through the palace towards the ice towers.

Whitefur was slumped over the Ice Queen and his weight held her still, but, as Eska approached, clasping the Frost Horn tight, the Ice Queen’s voice trickled out.

‘You and I could work together, Eska. Two great voices with the power to—’

Eska didn’t wait for any more. The Ice Queen was as weak as a rag doll now her power had been drained and Eska dragged her to her feet before shoving her towards the music box. She forced the Ice Queen on to the pedestal, then, with Flint’s help, she hauled the glass dome over the top and turned the small black key again and again, faster and faster, until her whole arm ached.

Music began, a clash of discordant notes this time, and, very slowly, the Ice Queen’s body began to break apart into tiny shards of ice.

Moments later, all that was left of her was a gown of frozen tears.

Eska rushed back to Whitefur and bent down beside him. ‘Thank you!’ she whispered. ‘You held the Ice Queen back so that I could call the tribes together!’ The Erkenbear didn’t reply and Eska’s hand stilled over his fur. ‘Whitefur?’

She leaned over so that she could see his other side. It was red beyond repair and only then did Eska realise what had happened. While she had been uniting the tribes, Whitefur had been dying.

Flint and Blu gathered close.

‘I thought Erkenbears couldn’t die,’ Eska said in a small voice. ‘I thought Whitefur was beyond the Ice Queen’s dark magic.’

She let her head rest against the bear’s as the tears began to fall and Flint and Blu did the same.

‘He fought for you out on the Driftlands last year.’ Flint’s voice was choked. ‘And he fought inside the palace tonight. He would have fought again, Eska, because his heart was good and true and brave.’

‘Erkenbears,’ Eska said through the tears. ‘I remember my pa’s stories about them now. Wanderers call them the Ever-Wandering Ones; they believe that even after they die their souls speak to us when fresh snow falls.’

And, though the thought of being able to speak to Whitefur again sent a glimmer of hope through Eska, it didn’t ease the pain and she cried on, for the life of her old friend.

They lay with their arms round the Erkenbear for a while longer, then the sound of pummelling footsteps filled the palace.

‘The prisoners in the ice towers – they’ve been freed!’ Flint breathed, forcing himself to his feet. ‘Ma!’

He rushed from the hall, hand in hand with Blu, and Eska would have followed had her ears not snagged on another sound.

‘Eska!’

Eska’s legs felt suddenly weak beneath her and her breath scudded through her throat. Because she recognised that voice . . .

‘Pa,’ she whispered, and then louder, as she rushed towards the arches where the call had come from, ‘Pa!’

Grabbing an abandoned knife from the ground, Eska leapt out on to the palace wall. She dug the knife into the ice there and used it to clamber up on to the top of the highest dome. Then she stood up tall.

‘Pa!’

Tomkin and Blade had scaled the ice towers and hacked open the door that blocked the prisoners in and now men, women, uncles, aunts and grandparents were pouring across the bridges that connected the towers to the palace and rushing into the arms of their children. Eska’s eyes flitted between the crowds, then they fixed on a tall man with broad shoulders who wore the furs of a silver wolf.

He was faster than the others over the bridges, but he didn’t rush into the palace. He grabbed a spear from the ground, snapped it in two, then he dug the spikes into the ice dome and began to climb towards his daughter.

Eska felt her heart shake. ‘Pa!’

Wolftooth hauled himself up on to the top of the dome, but he didn’t stop to gather his breath. He rushed towards Eska and scooped her up in his arms.

‘My little girl!’ he sobbed. ‘My precious little girl!’

And, as Balapan called out from the velvet sky above, Eska held on to her pa.