She’s still standing under her beam of light, only now she’s frowning. “Can you hear that?”

I listen. To begin with, all I can hear is the dripping of the icicles that surround us, but then I hear a scrabbling sound, and something else . . . panting. It seems to be coming from one of the tunnels.

I shake my head. These ice caves can do funny things to your mind, make you see and hear things that aren’t really here. But then a long, sinister howl echoes around us.

“RUN!” shouts Rose, and we follow Win into the tunnel. We’re plunged into darkness. Rose wrestles with her bag, then we hear the bottle clatter to the ground. We drop to our knees, feeling around on the cold floor. A volley of growls rings out behind us. The wolves must be in the chamber. It will only take them a few moments to discover which tunnel we’re in.

“Got it!” says Win, and he thrusts it at Rose.

Moments later light fills the tunnel and we are off.

Rose gasps. “We can’t outrun them!”

“We have to try,” I say, forcing my legs to move faster, ignoring the pain in my chest and focusing on the padding footsteps that seem to be getting louder.

Then Win shouts, “Up ahead . . . I can hear water!”

So can I. It’s moving fast, rushing and tumbling.

The tunnel turns and opens out on a ledge of ice. We slide to a stop just in time. Our path is blocked by an underground river. It races past us, deep and wide and impossible to cross.

“What do we do?” says Rose. “We’re trapped!”

Her words are followed by howls and we turn to see the wolves pouring out of the tunnel. They creep toward us like one creature, heads low, teeth bared, their claws skittering on the ice. They surround us, pushing us closer and closer to the river. When we’re teetering on the edge of the ice, our heels hanging over the water, they come to a stop. They wait, mouths hanging open, saliva dripping. One leaps at Rose, but a sharp whistle makes it slink back.

Hati is coming.

The wolves’ eyes dart to the tunnel and then back to Rose. Their tails curl under. They look like us, I think. They look scared.

Hati Skoll strolls into the cave. She walks up to her wolves and rests her gloved hands on two huge heads. The brown leather disappears into their fur.

She sees Rose hiding between me and Win and grins. “Caught you!” She sounds gleeful, like she’s playing a game. “Now you’ve got to join my pack.”