‘It doesn’t matter,’ said Elowen. ‘As long as it’s there. We aren’t too late!’

‘Yes!’ Tears of joy froze at the corners of Liska’s eyes as she cried them. ‘And all we have to do now is cut out the heart—’

She stopped in mid sentence, a horrible thought creeping over her like ice from the glacier itself. Cut out the heart. But what with? All she had brought with her was a pocketknife. They should have had axes, saws, shovels . . .

She fell to her knees, Lug toppling down after her.

‘What is wrong?’ Fishbone had been staring at the tree too. He scampered back as soon as Liska knelt, his furry brow creased with worry.

‘The heart . . .’ she said. ‘How are we going to get it out? We didn’t bring tools, axes . . . How could I have forgotten that? How could I be so stupid?’

‘Don’t worry,’ said Elowen, her voice as chirpy as ever. ‘Let’s just get to the tree. I’m sure a solution will present itself.’

‘Or we could ask her,’ said Fishbone.

For a horrid moment, Liska thought he meant Thresher, that the hunter might be standing right behind them ready to pounce.

But the little cat-person was pointing at the tree, at Nammu, to where a girl was standing, spear in hand. A girl with hair the colour of fire and eyes fixed right on them, poised in a warrior-stance, ready to defend her territory.

*

They started walking again, wary this time, staring at the fierce stranger waiting for them.

‘Who is she?’ Liska asked Elowen. ‘What is she doing?’

‘She must be one of the people that once lived in this place,’ said Elowen.

‘People lived here?’ said Fishbone. ‘Who would choose to be cold all the time when there’s warm rocks to snooze on in the sunshine?’

‘There were lots of people here once,’ said Elowen. She pointed to the ground around them, where the earth was still scarred with squares and circles – the marks of tents and buildings that must once have stretched out from the tree in a small city. ‘They wanted to be close to Nammu and its magic, just like the people of the other trees of light.’

‘What happened to them?’ Liska wondered. ‘Why would they leave their tree? Especially when the shadow tree that might kill it was gone?’

‘Some of them came to live in Almberg,’ said Elowen. ‘Others went to the east and west. They knew the end was coming. They just didn’t know how long it would take.’

‘Did they go to other trees of light? Are there more out there?’ Liska looked eastwards but could see nothing except more tundra stretching off into infinity.