They chose the Grey Man’s shoulder – partly because it was a flatter surface, but mostly because, when Blu tried to scale the giant’s nose to reach his forehead, the giant had sneezed and Blu had been coated in a thick layer of slime.

Eska, Flint, Blu and Pebble sat on the Grey Man’s shoulder with the sack of feathers, silently envying Balapan gliding above. The sky ahead was pink and the sea around the icebergs almost purple as the light finally faded. Eska swallowed. Somewhere out there was the legendary Frost Horn and time was running out to claim it.

The giant strode back quite some way from the cliff edge.

‘We’re sort of in a hurry,’ Eska whispered. ‘Aren’t you going the wrong way?’

‘You must never underestimate the wrong way!’ the Grey Man thundered. ‘Because more often than not it turns out to be the right way . . . Just with a few more bends in the road!’

Flint nodded warily. ‘Yet another detour . . .’

The giant spun round and Eska and her friends clung to the rocky crevices in his shoulder. Then the Grey Man took an enormous stride forward – then another and another – and Eska dug her fingers into the cracks in the stone.

‘Hold on!’ the Grey Man hollered. ‘It’s been a while since I made the jump and I’ve no idea if my back will hold out during the descent!’

A look of horror washed over Flint’s face, but Blu grinned.

‘Wheeeeeeeee!’ she shouted as the giant leapt from the cliff. ‘I tell Tomkin I jump with giant!’

They plummeted down, down, down with Balapan at their side – past the puffins, kittiwakes and guillemots crammed on to the rocky ledges – and Eska’s stomach lurched.

‘And run from wolves!’ Blu giggled.

The horror plastered across Flint’s face deepened and then they landed on the snowy beach with a very large, and slightly painful, bump.

The Grey Man dusted a clump of lichen from his leg. ‘Not bad, considering.’

Eska breathed out and as she watched Balapan preening her feathers nearby she thought how much less complicated life would be if she was an eagle. Still, they had made it down to the shore, a drop many of the Feather Tribe had died attempting, and before them now was the sea – dark purple and loaded with icebergs. There were harp seals and bearded seals dotted here and there on the flat icebergs nearby, but further out, on the bridges, leaning towers, columned arches and pyramids chiselled out of ice, there was nothing at all. Eska thought of her ma suddenly and wondered whether she had stood on this beach and swum in the waters that broke over it.

The Grey Man lifted the group from his shoulder and set them down by the shore. They listened to the creak and jostle of the icebergs moving.

‘The Frost Horn,’ the giant said quietly. ‘You’ll find it among the last of the Groaning Splinters.’ He paused. ‘I would say more but the truth is I don’t know any more. I just remember, many moons ago, that the greatest of the Sky Gods left it there after breathing life into Erkenwald.’

Flint glanced at the driftwood lying about the beach and swung his sack of feathers to the ground. ‘I have a plan, a rough one, for when – if – we get the Frost Horn.’ He sighed. ‘But how do we even get out to the furthest icebergs in the first place? That’s a jungle of ice – we’ll need a kayak to steer us through!’

The Grey Man knelt down beside them. ‘Or just a very convenient wind . . .’

He didn’t explain any more and minutes later the last of the colour drained from the sky and night crowded in. Eska’s skin prickled. There would only be a few hours of darkness – the nights were getting shorter with every day that passed – then dawn would break and they’d be just one day away from the midnight sun . . .

‘You can’t go on now,’ the Grey Man said. ‘It’s too dark and you’ll need a rest and food.’ Pebble snuffled in agreement. ‘But I’ll take you at first light.’

The Grey Man stepped back and only then did Eska notice the abandoned igloo behind him. The slabs of snow were slightly misshapen – battered over the months by the winter storms – but it was a good enough shelter for the night and the group hurried towards it.

‘I’ll keep guard through the dark,’ the Grey Man said, settling himself down on a rock by the shore. He dropped his legs into the water and smiled. ‘It’s good to be home . . .’

Flint and Blu laid out furs inside the igloo while Eska clambered up the cliffs with Balapan. The eagle cracked open the gull eggs and drained the yolks there and then, but Eska pocketed as many as she could carry and stole back to the igloo. She crept inside. This was a former Tusk home and yet, in the hour she had taken to forage for eggs, her friends had transformed the snowy dome.

Flint had a fire going and above it Blu had hung the magnifying glass infused with rainbow essence and, though from the outside the igloo looked just like a dark shape huddled at the foot of the cliffs, inside it glowed every colour possible. Turquoise danced over the roof, purple flickered across the floor and gold shone on the walls.

‘It’s beautiful in here,’ Eska whispered. ‘A pocket of Erkenwald not yet ruined by the Ice Queen.’

Flint cracked the eggs on to a flattened stone he had placed above the fire, then he looked at Eska.

‘We’re going to find the Frost Horn,’ he said. ‘However far out on the Groaning Splinters it is.’

‘But it’s not just finding the horn, is it?’ Eska whispered. She thought of Rook leading the Tusk guards towards the Lost Chambers. ‘It’s everything that comes after that – blowing it from the skies, getting the tribes to fight with us, stopping the Ice Queen from changing Erkenwald for ever.’ She looked down. ‘So many things to hope for.’

Flint nodded. ‘But think back to where we’ve come from. The music box, the Giant’s Beard, the Never Cliffs and the Grey Man outside guarding our sleep. It’s going to be okay.’

‘We find Ma,’ Blu said.

It wasn’t a question. It was a fact. And Eska realised then that hope moved quickly. It could burn inside you one minute and then, just when you thought you’d lost it, you’d find it shining in the hearts of your friends. She looked around the igloo. So long as one of them remembered to bring hope with them, perhaps things would turn out all right.