The tunnel becomes steeper. I wrap my arms around Rose’s legs and she grabs hold of my hair, and we don’t let go. It’s painful, and we can’t protect our heads, but at least the wolves haven’t followed us. The chute must be too steep. It drops away beneath us and in total darkness we slide around corners, twisting left, then right, all the time picking up speed. My foot hits a rock, sending a jolt of pain up my ankle, but I barely feel it because just then my head scrapes along a lump of ice.

We tumble over a lip of rock and then we’re flying through the air. We land with a thump. My face is pressed into ice, but most of my fall has been broken by Rose, who is squashed underneath me.

She groans and mutters, “Get off me, you lump!”

I stagger to my feet and despite the pain that’s throbbing through every part of my body, my heart lifts. We’re alive and we’ve lost the wolves! Their howls have faded away to nothing and now we are surrounded by a deep echoing silence.

“Conker bum!”

Ah, not quite silence. A spluttering blue flame pierces the blackness and I see Win’s grinning face and his half-snapped wand. His nose is bleeding and he has a purple bruise on one cheek.

“That,” he says, pointing his wand at the hole we’ve just fallen through, “was the coolest thing I’ve ever done in my life!”

He runs his floppy wand over us to check for damage.

“You’re all right,” he says, prodding my cheek. “Rose, you’ve going to have a black eye and you’ve got a cut on your chin, but basically you’re both fine.”

“Well, we’re not really fine,” I say. “Presumably we’re still being chased by wolves and that lunatic Hati Skoll, and we’re lost inside an ice mountain.”

“Presumably!” says Rose, imitating me. “Don’t be so negative, Arthur. For one thing, how do you know we’re lost?”

“Er, because we don’t know where we are. Are we in a cave, or a tunnel? We haven’t got a clue because our only light source is Win’s teeny-weeny flame.”

Win does an outraged gasp and his flame flickers out. “Your negativity has killed my magic!” he says.

“No, it hasn’t,” I say. “Your rubbish magic did that all on its own!”