Aaron must have seen it at the same moment, as he stopped in his tracks. “What the —”

  “It looks like a guard’s hut or something,” I said. It had a pointed top, three solid walls, and the third had an arched opening.

  Aaron was saying something, but I didn’t hear it. I was looking beyond the ice house — at a scene I had no words to describe.

  “Aaron,” I whispered.

  There were sculptures everywhere. Ice tables, ice pillars, ice chandeliers, even ice people — or ice heads, anyway. We couldn’t see their bodies from where we were.

  It was as though a whole team of ice sculptors had lived here for years, working nonstop before disappearing and leaving nothing but their work behind. Maybe that was exactly what had happened. I certainly couldn’t think of any other explanation.

  Aaron let out a low, whistling breath. “Wow!”

  I took two more steps and looked down at the statues again. That was when I realized something else.

  “The statues!” I said, my voice shaking as much as my knees.

  Aaron glanced down in the direction I was pointing. “They’re . . .”

  I looked at him. “I know,” I said. “They’re merpeople.”

  We stared at the mer-statues. They were so realistic. Some of them were sculpted sitting on boulders, others horizontal, tails out, as if swimming through the sea. Their tails were so intricate, their faces so lifelike.

  A sheen of some sort seemed to surround them all. “How on earth did they do that?” I asked.

  Aaron pointed toward the top of the sheen. “Look, it’s wavy, just like the surface of the sea.”

  It was as though the sculptors had created an entire world of merpeople, complete with the ocean. But why would someone produce such amazing art and keep it hidden in a place like this?

  I leaned forward to take a closer look, holding my crystal out in front of me to shed more light on the statues. I was about to take another step when Aaron screamed from behind me.

  “Emily! Careful!”

  He grabbed the back of my coat, stopping me from taking another step. As he grabbed me, the crystal fell from my hand.

  “Why did you —” I began. And then I looked down. We were on the edge of a precipice. I hadn’t realized.

  The crystal was still falling — and if Aaron hadn’t grabbed me, I would have gone with it. As I stared, I noticed something else, right in the middle of the display. The largest statue of them all.

  “Aaron!” I gulped. “Look at that!”

  He followed my shaking finger. “But . . . but that’s . . .”

  I felt as though the ice had crept into my throat, my chest, my stomach — it was inside the whole of me. There was no explanation for what we were looking at, none at all.

  Down below us, sculpted in the finest detail you could imagine, and more lifelike than anything I had ever seen, was Neptune.

  We stood, transfixed, staring at the Neptune sculpture and at the crystal, which was still glowing and had landed on the hazy sheen below.

  “Emily, this is creeping me out,” Aaron said in a whisper.

  “I agree. Let’s get out of here.”

  We turned to head back the way we’d come — but before we’d taken more than two steps, something stopped us in our tracks. It was a creaking noise, a bit like the sound we’d heard in the center of the mountain when the ice had begun to melt — only this was about a hundred times louder. It was coming from down below.

  I looked back. The sheen was beginning to dissolve in the exact spot where the crystal had landed. The crystal was burning a hole through the shimmering “sea,” carving a well that was growing deeper and wider by the second, glowing and sparkling as it drilled into the ice. As the well grew, something strange started happening to the statues within it. The ones nearest to the crystal began to thaw!

  “What’s going on?” Aaron’s voice had an edge of panic I’d never heard before.

  “I have no idea,” I said. Part of me wanted to run away, wanted to get the heck out of there as fast as I possibly could, wanted to turn back the clock and never let Neptune talk us into this crazy mission in the first place. But another part of me couldn’t move. I couldn’t take my eyes away from what was happening.

  Bit by bit, the sheen was turning into water. Shapes that had been beautifully sculpted merpeople only minutes earlier began to writhe and stretch and swish their tails. Sculpted fish came to life and began swimming in the well of water opening up around them.

  Soon, the well had spread into something very similar to the shape of the crystal itself. A giant, jagged droplet of space in the ice, big enough for about six or seven merpeople and countless fish to start swimming in.

  The melting seemed to have stopped. Around the crystal-shaped well, everything else was still ice, apart from tiny watery splinters. Inside it, the scene was very different. Merpeople swam toward each other, hugged, shook hands, smiled and laughed. The fish swam frantically around, forming shoals to explore their new giant fishbowl together.

  And then I saw something right at the edge of the melted bowl. It looked like a small shark. It was swimming upward through one of the splinters in the ice — heading in our direction. Not only that, but it had some kind of weapon with it. It looked like it was carrying a long spear — on its head!

  “Aaron, what’s that?” I gasped.

  “I’ve got no idea — but I think it’s seen us.”

  He was right. The shark was heading straight for us — and it didn’t look friendly. Nor did the spear that I could now see was at least as long as its body.

  “Let’s go!” Aaron yelped.

  I didn’t need to be told twice. In fact, I didn’t even need to be told once. I was already running out of that creepy place as fast as my shaking, slipping legs would carry me.

  I don’t know how we did it. Maybe terror is good for improving your sense of direction. But we ran and ran, hurling ourselves along rocky tracks, pelting down forks in the tunnels without even thinking, until, eventually, the tunnel began to feel like the one we’d come down in the first place.

  A tiny glow of light began to emerge ahead of us. We’d done it! We’d found our way out!

  Except, once we were outside the mountain, nothing looked familiar. This wasn’t where we’d come in. We came in underwater. This entrance had water lapping at the rocks, but it wasn’t deep enough to swim in.

  We waded through the water until it grew deeper. Then we threw ourselves in and let our tails form. We swam close to the surface, looking around for something familiar. The fjord opened up to a wider stretch of sea. Over the other side, there was a port with buildings and ships.

  “Emily, look over there,” Aaron said, pointing at the port. I squinted into the sun — which was dazzling my eyes even though it was the middle of the night! And then I noticed it. A ship. Our ship! “Please tell me that isn’t a mirage,” I said.

  Aaron smiled. “I remember now. In the brochure, it said there was a midnight concert tonight, at a town on the other side of the glacier.”

  “We’ve been all the way through the mountain range and come out on the other side?”

  Aaron shrugged. “It’s the only thing that makes sense. We’ll need to hurry, though. The program said the ship was sailing again at two.” He glanced at his watch. “It’s half past one. We’ve got thirty minutes.”

  We swam harder than I’d ever swum in my life. Finally, we pulled ourselves out of the water in a rocky inlet, just out of sight of the boat, and waited for what felt like forever for our legs to reform. Then we ran like crazy and reached the ship, panting and breathless, just as they were about to start lifting the gangplank.

  “Got in by the skin of your teeth, there,” the steward said with a smile as we showed our passenger cards and stepped inside. “Had fun?”

  “Mm,” I said, not even bothering to try to sound convincing.

  As the large doors slid closed behind us and the ropes were thrown up to the ship
from the men on the dock, I could have cried with relief.

  “We made it,” Aaron said. He put his arms around me, and this time, I didn’t try to stop him.

  “There you are!” Mr. Beeston’s voice made me leap out of my skin — and out of Aaron’s arms. “I’ve been looking for you all night. Pacing corridors, searching the coastline, coming back here every ten minutes.”

  He stopped and looked properly at us. I imagine the combination of grime and gravel, messed up hair, torn clothes, and a hundred different emotions on our faces probably didn’t make for the most attractive sight.

  “I’m forgetting myself — forgive me,” Mr. Beeston mumbled. “I’ve just been so concerned. Are you two all right?”

  Aaron nodded.

  “Just about,” I said.

  Mr. Beeston fiddled with a loose strand of hair, flattening it over his head. As I looked at him, I realized he looked exhausted. It was only then that it hit me: it was the middle of the night. Suddenly, I was so tired I wasn’t even hungry anymore. I just needed sleep.

  “I have to get to bed,” I said.

  “Of course, of course!” Mr. Beeston said hurriedly. “We can catch up in the morning.”

  We made our way to the corridor. Aaron and Mr. Beeston’s cabin was in one direction; mine was in the other.

  “Millie knows nothing about this,” Mr. Beeston said as we walked. “I told her you were spending the evening with a family who had children your age.”

  “All this time?” I glanced at a clock on the wall. It was twenty past two. Mr. Beeston waved a hand as if to shake my question off. “Different rules apply when it is daylight for twenty-four hours,” he said. “Anyway, I went past your cabin earlier and you could hear her snores from outside the door. I don’t think she will even notice you come in.”

  I stared at Mr. Beeston. I still couldn’t get used to the idea that the man who had spent the first twelve years of my life spying on me was now our greatest ally. “Thank you,” I said simply.

  He fiddled with a button on his jacket. “Get to bed,” he said softly.

  We parted company and I headed back to my cabin. I gently opened the door. Mr. Beeston had been right. Millie was lying flat on her back, arms spread out, mouth wide open, snoring like a horse.

  At any other time, the sound might have bothered me. But after everything we’d just been through, nothing was going to keep me awake.

  Five minutes later, I was in my bed, fast asleep, and for all I knew, snoring just as loudly as Millie.

  I dreamed I was swimming in the roughest sea I’d ever known. Up, down, thrown all around. Wave after wave kept washing over me, pulling me down into the belly of the ocean and then spitting me out again.

  A sudden lurch to the side woke me with a start.

  I opened my eyes and looked around. Just a dream.

  Millie was already up. She was sitting on the end of her bed, peering into the mirror as she put her eye makeup on. “Morning,” she said with a smile. “A little early for you, isn’t it?”

  I looked at the clock. Six thirty! I was about to say something when the boat dipped and Millie fell sideways.

  “Bit rough out there this morning,” she said, putting her lipstick away.

  Lying down wasn’t feeling very pleasant anymore. I dragged myself out of bed and rubbed my eyes. The boat dipped again, this time taking my stomach with it.

  “Millie,” I said. “I need to go outside.”

  We got dressed and went up to the roof deck. There were a few people already out there. They obviously weren’t enjoying this morning’s swells, either.

  I looked around. “Hey, look!” I pointed to the back of the boat. Aaron and Mr. Beeston were standing separate from the others, gripping the handrail and talking close together. We made our way over to join them.

  Things took a turn for the worse as we crossed the deck. The ship suddenly seemed to rise almost vertically on a massive wave. Then it careered down the other side, as if we were on a roller-coaster ride.

  We made it to the back just in time to grip on to the railings.

  Aaron and Mr. Beeston stumbled over to join us. Looking out at the horizon, it seemed the ocean had erupted. The sea was like a mountain range, rising and falling with enormous peaks and troughs. White froth foamed angrily over the top of every peak.

  I turned to Mr. Beeston. “What’s going on?”

  “I have no idea,” he said somberly. “Usually, a storm like this means only one thing.”

  He didn’t even have to say the word. I knew what he meant. This had to have something to do with Neptune.

  “But why?” Aaron asked, following on from my thoughts as though I’d spoken them out loud.

  I thought back over the events of the night. What did any of it mean? Had we gotten the whole thing wrong? Was Neptune angry?

  Ding dong ding! “Ladies and gentlemen, we are experiencing some heavy weather,” a voice crackled over the loudspeaker. “We advise all passengers to return to their cabins until further notice. We shall be turning the ship around and returning to our last port, so that we can find a safe harbor until this weather passes. I repeat, please return to your cabins immediately and remain there until we dock, in approximately one hour. Thank you and we apologize for any inconvenience.”

  We inched our way to the door and waited behind the other passengers to go in. Millie went first, then Mr. Beeston, then Aaron. I was about to follow them when something caught my eye. Something in the sea.

  Millie was holding the door open for me.

  “I just got something in my shoe. Need to get it out. I’m right behind you.”

  “I’ll wait,” Millie said, swaying as she held the door.

  “No, you go,” I said. “I’ll only be a second.”

  “OK, but be quick,” she said. “I don’t want you out here while it’s like this.”

  As Millie let the door close, I looked around to make sure no one was watching, then I carefully made my way to the side of the boat. I stared so hard at the peaks and troughs of the swells that my eyes began to water. Had I imagined it?

  I was about to leave when I saw it again. A tail! Flashing up in the water before disappearing again. What was it? A shark? A whale?

  Come on, come on, I whispered, desperate to find out what it was before one of the ship’s officials came out and ordered me back to my cabin.

  And then I saw it again. It was closer this time. And it was familiar. And even though I had no idea how in the world I could possibly be right, I knew exactly who that tail belonged to.

  Shona!

  Suddenly, she poked her head above the water and waved an arm at me. Then she pointed to the harbor we were heading for.

  “See you there?” I called.

  Shona nodded, and with a flick of her tail dived back under the water.

  I went inside to join the others, my mind spinning with confusion — and with excitement. My best friend was here!

  The excitement was tempered only by one fearful question.

  Why?

  The moment the ship docked in the port, I was in the water. I didn’t even wait for the doors to open. I hung around at the back of the ship on level three, the lowest one with an outside deck. I looked around, making sure there was no one near. And then, as gracefully and silently as I could, I dived into the choppy water.

  She was there in moments.

  “Shona!”

  “Emily!”

  We fell into each other’s arms. “You are real, aren’t you?” I gasped. “It’s not a dream?”

  “It’s not a dream,” Shona said seriously. “But when I’ve told you why I’m here, you might wish it were.”

  Despite Neptune’s potion on my body, I turned cold inside. “What is it? Why are you here? How did you get here? How did you know where we were?”

  Shona held up a hand. “Whoa! One thing at a time.”

  I took a breath. “OK. How did you get here?”

  “It wasn’t the easiest thi
ng in the world,” she admitted. “I swam some of it — and caught a few lifts.”

  “Lifts?” I gasped. “Who with?”

  “A couple of dolphins to begin with. They were great. Then I had to swim a bit more. That bit was quite tough, as the currents weren’t going my way. Luckily a lovely blue whale spotted me and helped me out. Then finally, a pod of orcas brought me the last couple of hundred miles.”

  I stared at Shona. I literally didn’t know what to say. She had done all this — for me? She’d either missed me really badly, or something was very, very wrong.

  “Do your parents know you’re here?” I asked.

  Shona blushed. “They don’t know about your trip or anything, so I told them I was going to stay with you on Fortuna for a few days. I hate lying to them, but it was important.”

  “How did you know where we were?” I asked.

  Even if I’d had a hundred guesses as to what her answer might be, I would still never have gotten it right.

  “Neptune told me,” she said.

  Before I could do anything more than let my jaw drop open, she went on. “Well, he didn’t actually tell me. At least, he didn’t mean to tell me.”

  “Shona, my head is spinning enough without riddles. What’s going on? What are you talking about?”

  “I kept the phone on me the whole time. Even when I went to bed, I had it beside me on my pillow. And then something woke me up just after I’d gone to bed last night. It sounded like waves crashing over a pebbly beach — and it looked like stars glinting and shining. But it was the shell phone calling.”

  “Neptune — trying to get in touch with us.”

  Shona nodded. “I picked up the shell, and straightaway I heard him speaking. I couldn’t make sense of it at first — it was like he was just shouting random words down the phone.”

  That sounded familiar. I still had many of Neptune’s early morning ramblings bouncing around in my head. “What kinds of things did he say?”