Moll, Gryff, Siddy and Frank clung on in terror as the giant’s voice boomed out.

‘Who disturbs the Ancient Ones?’

The voice was so low and loud that its vibrations sent whole chunks of snow sliding off the peaks around them. The giant took a huge stride forward and Moll felt her body slam against his rocky thigh. She gripped tighter, hardly daring to breathe, and glanced up. The giant’s torso loomed above her, a tower of mighty rocks, but it was the face that scared Moll most: great caverns for eyes, a jagged ridge for the mouth and shards of ice for hair.

She could feel Siddy shaking beside her. ‘What do we do?’

But the answer didn’t come from Moll. Again the giant bellowed and the sound echoed across the mountains, filling the sky and the sea and every living thing around them.

‘Arise, Ancient Ones!’ it cried. ‘There are imposters in our midst and they have broken our slumber.’

All around them the mountains juddered, shaking off clumps of snow before rising up into stone pillars. Ten giants lumbered forward, stepping over ridges as if they were pebbles, and the words ran dry in Moll’s throat. The giants were so enormous they could have perched on the Stone Necklace and paddled their bouldered feet down in the loch below.

Moll pressed herself into the giant’s leg, her eyes closed. ‘Don’t move,’ she whispered to Siddy. ‘Whatever you do, don’t move. They might not have seen us yet.’

The giant turned his body this way and that as he searched for the intruders and, with each swing, Moll, Gryff, Siddy and Frank swayed back and forth, fingertips and claws clutched tight. He stooped down and peered beneath a boulder before flinging it aside and, with her heart thundering, Moll opened one eye. Her muscles tensed. Frank was climbing out of Siddy’s pocket and to Moll’s horror she saw the ferret had interpreted the advancing giants as an invitation to play. Frank dropped down to a narrow ledge – the giant’s knee perhaps – and began to dance.

‘There!’ a giant roared.

The voice was female, but it was loud and fierce and Moll’s insides churned as she realised who it had come from: a giant to the right of them with long, daggered icicles hanging down either side of her face and knuckles the size of bricks that dragged across the ground. Her mouth opened, wide and black like the entrance to a cave.

‘On your leg, Wallop!’ she screamed. ‘They’re on your leg!’

The giant they were clasping on to, Wallop, glanced down and Frank scampered back up to Siddy, Moll and Gryff who then shrank as far as they could into a crevice. But there was no escaping now.

‘Two smidglings, a wildcat and a ferret?’

Moll felt the rush of Wallop’s breath on her cheeks, as cold as the bitter north wind, then the giant swung a hand towards the group, swiping them clean off his leg and into his rocky palm. He unfolded his fingers and drew his prisoners up to his face, squinting into the fading light. Moll clung to Gryff. Wallop’s mouth was a den of darkness and, as he raised the group up to his nose and sniffed them, Moll’s whole body slid towards it, sucked in by his heaving breath. Then Wallop’s face scrunched, his eyes narrowed and he roared, sending Moll, Gryff, Siddy and Frank tumbling back over themselves against his fingers.

‘They have the Oracle Arrow!’ he hollered.

There was a rumbling and a grunting among the other giants, then one raised its fist. ‘Then they must be the ones who stole the Ancient Book from our cave too! Thieves! Thieves!’

Moll staggered to her feet. ‘We haven’t stolen your book!’ she shouted. ‘And we only have the arrow because—’

The female giant strode forward and the icicles around her face jangled. ‘Eat them, Wallop,’ she said.

Another giant nodded. ‘Munch their bones!’

The giants’ rage grew.

‘Chomp their stupid brains!’ cried yet another.

‘Chew their pointless toes!’ It was the female giant again, bent on absolute brutality.

Wallop raised a hand and the chanting faded. ‘We are the Keepers of the Ancient Book, the manuscript that holds the full story of the old magic,’ he said. ‘We are not barbarians.’ He glanced at the female giant who looked rather disappointed. ‘Please remember that, Petal. These smidglings deserve a fair trial.’

Siddy rose to his feet beside Moll. ‘Thank you – thank you!’

The giants sat down on the mountaintops in a circle around Wallop, who held his prisoners up in his hand.

‘Smidglings, you are charged with stealing the Ancient Book and the Oracle Arrow. How do you plead?’

Moll looked at Siddy and together they said, ‘Not guilty.’

Siddy took a step forward. ‘We’re trying to protect the old magic – just like you. We found the arrow stuck inside Murk, the creature in the loch, and we haven’t even heard of your book before. You need to believe us so that we can stop the last Shadowmask from conjuring the eternal night!’

There was a momentary silence and all Moll could hear was the shuffle of falling snow. And then the giants began to laugh.

‘Murk lives one hundred years deep!’ Wallop guffawed. ‘A couple of smidglings like you couldn’t have summoned her from all the way down there. So, it seems you are liars as well as thieves . . .’

‘Gobble their bottoms!’ Petal roared. ‘Snaffle their earlobes!’

Moll tried to keep calm. ‘But we did summon Murk!’ she cried. ‘The old magic sent us clues to follow and, even though the last Shadowmask buried that arrow one hundred years deep, we found it!’ The two rocky ledges above Wallop’s eyes lifted and Moll spun round to Siddy. ‘They don’t believe us, Sid! After everything we’ve gone through, they think we’re making this up!’

Siddy could feel Moll’s temper rising. ‘Don’t do anything rash, Moll,’ he begged. ‘We’ll make them understand.’

But Moll was way past rash. Out came the catapult, in went the stone and, with fiery eyes, she raised her weapon towards Wallop’s forehead. ‘Listen here, Wallop!’ she snarled. ‘You better put me and my pals down or—’

The giants were on their feet again, punching their fists in the air.

‘Eat the angry smidgling first!’ Petal roared. ‘Swallow her whole!’

‘But – the – the trial!’ Siddy stammered. ‘You promised us a fair trial!’

Wallop grunted. ‘That was before missy here got out her catapult.’

Siddy yanked Moll’s weapon down. ‘Apologise!’ he cried. ‘They’re giants, Moll!’

Moll wrenched her arm free and drew back on her catapult pouch. ‘He called us liars – after all we’ve done to protect the old magic!’

Siddy flung himself against Moll. ‘Don’t do this!’

But she wrestled her arm free, pulled back on her catapult – and fired. The stone clipped Wallop’s forehead, then clattered off his body before dropping to the ground.

Siddy bit his lip. ‘Oh, Moll, why do you never learn . . .’

The giants stamped their feet then threw back their heads and bellowed.

‘Squash them!’

‘Trample them!’

‘Flatten them!’

Petal clapped her hands. ‘Mince them in the snow! Gobble their guts!’ She was in her element now.

Wallop drew his hand up to his face and then opened his mouth. Siddy hugged Frank, Gryff began to hiss and then Moll grabbed Siddy’s arm.

‘Listen!’ she cried.

Above the hollering giants was the unmistakable sound of a horn. It blared out across the mountains and Wallop’s hand stopped in mid-air. Next came a thundering of hooves. And then voices shouting. Moll’s heart leapt. Could it be? The other half of a promise made on the moors before the Lost Isles?

And then, tearing over a ridge to the east of them, only just visible in the dusk, came a woman with ginger hair and a crossbow slung over a tartan cape, and a young man, dark-haired, full of fight, clasping a pistol.

‘Aira!’ Moll screamed. ‘Domino! Help us!’