But letting Toklo and Lusa face the danger alone was unthinkable. Every pawstep an effort, Kallik padded into the den behind them. She stood in a small inner den, brightly lit, with white walls and doors leading off on all sides. Pushing down her fear, she followed her companions as they crept forward through one of the inner doors, which led into a long passage.

‘How do we know where to find Ujurak?’ she whispered as she caught up to the others.

‘We don’t,’ Toklo replied. ‘We just keep looking.’

‘Good plan,’ Lusa muttered.

They were passing closed doors on either side; Kallik guessed that they led to other little dens. She didn’t think Ujurak could be inside one of them; she had picked up his scent again, once she was calm enough to check, but it was still some way off.

Partway down the passage was another closed door; its frame was filled with the transparent stuff, and Kallik could see that the passage continued on the other side.

‘Do you know how to get through there?’ she asked Lusa.

While she was still speaking, the door slid open, just like the one that had let them into the den. Is it another trap? she wondered.

Then Kallik heard a door open behind her, followed by a loud scream. She whipped round to see a female flat-face in a white pelt standing in the doorway of one of the little dens they had passed. Instantly the flat-face ducked back inside the den, and Kallik heard the door slam.

Almost at once another door opened; a flat-face male popped his head out and withdrew again. His door also shut with a bang.

‘They know we’re here,’ Toklo snarled. ‘We’ve got to move now!’

Barely able to think for fear, Kallik bounded beside her friends, through the terrifying door and on down the passage. After a few pawsteps, she heard the door swish shut again. It was a trap!

But there was no time to think about that, or to worry about how they were going to get out again. A harsh ringing sound broke out all around them, and they ran even faster, skidding along the smooth passage floors.

‘This way!’ Toklo gasped.

He led them up a steep slope with chunks cut out of it, which made it easier to climb. Ujurak’s scent was growing stronger now. But the flat-faces will catch us first!

At the top of the slope they hurtled down another passage, only to skid to a halt as a flat-face with a firestick appeared at the other end.

‘Down here!’ Lusa dived down a side passage.

Kallik heard the crack of the firestick and glanced back to see a dart hit the wall before she pounded on.

‘They’ll put us to sleep!’ she gasped. ‘They’ll take us to the place where the hungry bears are kept!’