We walked through the woods to the other side, and when we came out I saw that the sky was a dark pink and looked heavy with snow. And it suddenly felt much, much colder.

“Where are we going exactly?” I said as Kitty turned left and headed down a hill. I was struggling to keep up with her.

“There’s an old family chapel down in the valley. I haven’t been there in years. In fact, I completely forgot there was one.”

I burst out laughing. “How can you forget you’ve got a chapel? Kitty, you’re not of this world!”

She looked around and her face dropped. I turned to see what had made her frown and saw the corner of a building. It must have been her house. The brickwork was gray and dark, but I could only see a fraction of it; the rest of the house was hidden by tall trees.

“Is that your home?” I asked.

She nodded and turned away quickly. “Come on, the chapel is over there. Look!”

Kitty pointed. Nestling in the dip of the hill was a little brown church. It was surrounded by an old stone wall that had crumbled in places.

I jogged to catch up with her. I remembered now that Mum had said the big house had its own chapel. She’d said it when we were hitting the rug with our sticks in the garden; she’d said we’d seen it when we’d stayed before.

It was starting to sleet, and the cold, freezing rain hit my face like pinpricks.

Kitty came to a break in the wall and clambered over the pile of stones. I looked around and saw a huge tree with a trunk the color of hot chocolate. Its roots were twisted and gnarled and its canopy of green looked like a giant umbrella.

“There it is,” I said. “That’s your yew.”

Kitty headed straight toward it. “These roots are worse than the ones in the wood. I’m never going to be able to dig here.”

I walked around the tree, trying not to twist my ankle in the tangled wood. “Maybe it’s not buried at all. We should look in the gaps and see if he’s hidden something in there. Be careful though, it might look nice, but this tree is really poisonous.”

I looked in all the crevices.

“It might not even be here anymore, Kitty. It might have just rotted away.”

Kitty scowled. “Of course it’s still here. I’ll start looking around this side.”

I crouched down and peered into all the little holes that the yew tree’s roots had created. I don’t think I’d ever been this close to one before. It really was very impressive. Kitty was around the other side of the tree, and the trunk was so wide I couldn’t even see her.

“Anything?” I called.

“No … nothing. Wait. Hold on—I think there’s something …”

I scrambled around the side just as she was poking a stick into a hole. She scraped at it a few times, and then finally something appeared. It was a little wooden box. She dropped the stick and grabbed it.

“I don’t believe it! We’ve found it! Oh …”

She opened the box and a piece of paper fell onto the ground, which she picked up, smoothed out, and read:

She looked at me. “Any ideas?”

I shrugged. “No. But I think I’m going to go back now. My parents will be wondering where I am.”

I wasn’t comfortable being out when Mum could arrive at any moment. I turned and walked back the way we’d come and Kitty followed, still holding the clue in her hand.

“Search for an I and an H. What do you think that means? Shall we have a look in William’s cottage? Maybe it’s something to do with a book.”

I grunted as I scrambled over the slippery, broken wall.

“Slow down, Nate. You’re going too fast,” she said as she tried to keep up with me. “What’s the hurry? We need to talk about the clue.”

I ignored her and strode toward the woods, but she quickened her step and jogged alongside me.

“We need to think where we should look next. Do you have any ideas?”

I stopped when I got to the trees. “No, but good luck with it all anyway. I’m sure you’ll work it out,” I said, and I began to jog away.

“Shall we check the cottage now?” she asked, catching up with me. “It could be in there. I really think we should check in the books.”

I stopped and turned toward her. “Look. I think what you’re doing with trying to solve this riddle is really great and all that, but I must get back. On my own.”

Kitty frowned at me, and then her face softened as she looked at something past my ear. “Oh look! Your parents are here!”

I couldn’t see properly through the trees, but I could definitely hear something. It sounded like a car traveling really slowly. Tires were scrunching along the frozen dirt track. Mum was back! I began to run.

“I’ll come back tomorrow at ten!” Kitty shouted as I disappeared through the iron gate and into the cottage garden.