“You’re my best friend,” I said simply.

  Shona smiled and threw her arms around my neck. “You’re the best best friend in the world,” she said.

  I knew I wasn’t, especially considering how much I’d neglected her lately. But I was really glad she still thought I was. I silently promised myself I would be a much better friend when this was all over.

  Shona swished her tail and dived under the water. “Come on,” she said. “Let’s go back to my house. I bet the crab cakes are done by now.”

  And for the first time all week, as Shona and I swam along, chatting about all the trivial details of our lives, I briefly forgot about Neptune and his nightmares.

  Friday morning came around far too quickly.

  Neptune had told us to wait at the end of the pier. He’d organized a boat to pick us up and take us to where the cruise ship was waiting; it was one of those underwater pellet-shaped things that was half speedboat, half submarine. In any other circumstances, the adrenaline coursing through my blood would have been because of excitement. Not today. My body was shaking with nerves.

  “It’s going to be OK,” Aaron told me.

  Mom was on the other side of me. She put her arm around my shoulders. “Hey, cheer up, you two — anyone would think you were being sent off to war, not on a vacation!”

  She had no idea how close to the truth she was.

  “Yes, of course, ha, ha,” I said, forcing a jolly laugh into my voice. “I’m just sad to be leaving you.”

  “Me too, sausage,” Mom said, giving me a squeeze. I could see how difficult she was finding it, and how hard she was trying not to show it. “You’ll be back soon enough, though, won’t you?”

  “We’ll be back before you know it!” Mr. Beeston chipped in, coming up fast behind us. “And don’t worry,” he added. “I’ll be there to look after them all the time.”

  We reached the end of the pier just as Dad popped his head up from under the water. “It’s here,” he said.

  A moment later, the boat rose high enough for us to see a door open at the top.

  I turned to give Mom one last hug and pretended not to notice the tear on her cheek wetting my own face as she held me close.

  And then Aaron and I headed over to the ladder at the end of the jetty.

  “WAAAAIIIIT! Hold on!”

  I turned to see someone running down the jetty toward us, a suitcase with clothes bursting out of it in her hand. Millie!

  “Wait for me!” she shouted. “I’m coming, too!”

  She caught up with us and, panting for breath, explained. “Archie knows someone at the boat company, and he managed to snag me a place! Isn’t that great?”

  “Well, yes, it’s brilliant,” I said. “But how come? I don’t understand.”

  “He’s so well connected with his work. He said it was his gift to me because I’ve been under so much pressure lately.”

  Millie had been under pressure? It was the first I’d heard of it.

  “My bad dreams, and starting the new class and everything,” she explained stiffly, seeing my surprise. “Anyway, you know how romantic he is — always surprising me with this, that, and the other. So he arranged it. I just have to do a few tarot readings and a chakra session or two for the crew, and the captain said I can come!”

  “Millie, that’s wonderful,” Mom said. “I’m glad you’ll be there to keep an eye on them and make sure they’re OK.”

  Mr. Beeston coughed pointedly.

  “As well as the fine job that Mr. Beeston will obviously be doing,” Mom added quickly.

  “Hmm,” Mr. Beeston said. “I suppose it can’t do any harm having two of us to watch them.”

  “Exactly.” Millie beamed. “Right, let’s go.”

  She passed her suitcase to Aaron and he clambered down the ladder with it above his head.

  And then we were on the submarine, waving through the door at the top till Mom and Dad and Aaron’s mom were specks in the distance.

  A voice came over the loudspeaker. “Everybody inside. Going under.”

  We closed the door and took our seats down below.

  This was it, then. After all the talking, the planning, the preparing — we were finally on our way to the world of Neptune’s nightmares.

  I have to confess, I almost forgot about the whole dangerous mission thing once we’d left Neptune’s submarine behind and boarded the cruise ship.

  It was AMAZING! Easily the biggest boat I’d ever seen. It was more like a small town. There were eight levels, with balconies going all the way around on a couple of them, and a roof terrace with two hot tubs and a swimming pool. Inside the ship there was an elevator that took you between decks! The restaurant served the biggest, fanciest, and most delicious meals you could think of. And the cabins — well, they weren’t huge, but they were comfortable and clean.

  I was sharing with Millie, and Aaron was sharing with Mr. Beeston. As Millie’s place had been so last minute, she’d actually been assigned a tiny cabin on the floor with all the staff. Millie being Millie, it hadn’t taken her long to fix things so that she got to share my bigger one, with its porthole on the side, instead. I didn’t mind. To be honest, it would have been a bit lonely on my own.

  All in all, it was pretty fantastic. If we actually had been here for a vacation, I imagine it would have been the trip of a lifetime.

  “Oooh, look at this one,” Millie said. She was flicking through the brochure of excursions that the company ran throughout the trip. “Sea eagle safari. That sounds good, doesn’t it?”

  I sat down next to her on her bed and looked at the brochure over Millie’s shoulder. Journey with us into sea eagle territory — and don’t forget your camera! it read. There was a picture of about twenty people on a small boat, a giant eagle flying toward them with a fish in its talons. The eagle’s eyes were black and hard. They seemed to be staring right off the page at me. I shivered. “Not sure about that one,” I said.

  “ATV safari?” Millie suggested, turning the page.

  “Hmm, maybe.”

  She flicked over another page. “Glacier trip?”

  My heart did a forward somersault into the air as I looked at the picture. The mountains, the lake, the glacier — I’d never seen them before, but I knew them.

  It was the place that Neptune had described.

  I tried to speak, but my throat suddenly had a large block of ice jamming it up. Instead, I just pointed at the picture and nodded.

  Millie looked at me. “You want to go on the glacier trip?”

  “Mmm!” I said, nodding again.

  “Not sure I’m interested in that one, myself,” she said. “Maybe Mr. Beeston can take you.” Then she licked a finger and turned the page, moving on to the rest of the excursions.

  I cleared my throat and found my voice again. “I’m going to see what Aaron’s up to,” I said as casually as I could.

  Millie closed the brochure. “OK, dear,” she said. “I might call Archie while you’re gone.”

  “Call Archie? What do you mean?”

  Millie reached into her bag and fumbled around. Eventually, after pulling out packets of tissues, notebooks, pens, and jars of strange-looking pills and scattering them across the bed, she found what she was looking for. A shell like the ones Neptune had given to Aaron and me — in shimmering green.

  “Where did you get that?” I gasped.

  “Archie gave it to me,” she said, hugging the shell. “Said it would help him to not miss me so much. It’s magical, you see. We can talk to each other with it.”

  “But how —”

  “Oh, I know. He’s a bit naughty, really. They’re only supposed to be used for top-level emergencies. But he said us being apart is a top-level emergency. He told me to call him and keep him up-to-date with what we’re all doing. He’s so romantic!” Millie sighed. “He did say I should be careful about using it, though. He might get into trouble if we’re caught using them just to whisper love messages to each othe
r.”

  I tried not to make a face. I really didn’t want to think too much about Millie and Archie’s love messages.

  “I suppose I shouldn’t call him right now,” Millie sighed. “Like he said, I’ll wait till I really need to.”

  With that, she kissed the shell and put it back in her bag.

  “Right,” I said. “I’ll see you later.”

  I left Millie to the rest of her unpacking and went to find Aaron. We’d only been apart for an hour, and already I had so much to talk to him about: the glacier trip; Archie giving Millie one of those shells; in fact, him sneaking her onto the trip in the first place. What exactly was Archie up to? The questions swam around in my head as I made my way to Aaron and Mr. Beeston’s cabin at the opposite end of the boat.

  I bumped into Aaron in the corridor.

  “I was just coming to see you!” we said in unison.

  Aaron grabbed my hand and pulled me over to a couple of seats in a recess of the lounge. “We need to talk,” he said. He had the excursions brochure on him. “Look,” he said, opening it on the page I’d just been looking at.

  “I’ve seen it,” I said.

  “That’s it, isn’t it?”

  I nodded. “I’m pretty sure it is.”

  Aaron pointed at the page. “Have you seen the date of the trip?”

  I followed his finger. My mouth fell open. “But that . . . but that’s . . .”

  “I know,” Aaron said. “It’s tomorrow. We’ve got one night to prepare ourselves.”

  “Listen to me.” Mr. Beeston was doing his best to talk quietly as the three of us huddled in a corner of the ship, waiting for the small boat that was coming to take us on the glacier trip.

  “We haven’t had a chance to talk properly yet, and we haven’t got much time now, but I need to tell you a few things.”

  We leaned in and listened.

  “I know this isn’t a vacation,” Mr. Beeston began. He looked searchingly at us both. What should we say? Admit he was right, or deny it? What if he was trying to trick us?

  “Why do you say that?” Aaron asked carefully.

  Mr. Beeston tutted. “Look, we don’t have time to play games, so I’ll tell you exactly what I know about my role. I’m not asking you for information. I’m here for you. All right?”

  I nodded. “All right.”

  “Neptune has sent you both here for a reason. What, exactly, that reason is, I don’t know. I am not privy to the details, and I am not asking you to tell me them. What I do know is that I am here to give you whatever support I can while you carry out your task to the best of your ability.”

  “OK,” I said guardedly. “Go on.”

  “I know that you have to leave the ship and that I may have to cover for you while you are gone. I know that if there’s anything you need from me, all you have to do is ask, and if I can provide it, I will.” He paused. “And I know that if Neptune believes that the two of you are worthy of his trust and are up to the challenge he has set you — then I believe it, too.”

  For a moment, I couldn’t speak. My throat had shriveled up, and I think I must have gotten something in my eyes, as they’d started watering.

  He lowered his voice even further. “And I know that it is here that you have to leave us.”

  “How do you know that?” I asked.

  “I didn’t get to the position I hold today without learning how to read subliminal signals,” he said mysteriously.

  Sub — what?

  When we both looked at him blankly, he went on. “Both of you look rigid with fear — and have since this morning. It isn’t rocket science.” He looked around at the tourists smiling and laughing as they waited for the boat to come and take them out for the afternoon. Then he lowered his voice. “You’re not only here for the afternoon’s glacier trip, are you?”

  Aaron and I exchanged a look.

  “OK, you’re right,” Aaron said. “We have to go to the glacier, but we’re not sure where we have to go next. We have to . . .” He stopped and looked at me, then, reddening a touch, turned back to Mr. Beeston. “I don’t know how much we can tell you,” he finished.

  Mr. Beeston waved a hand. “It doesn’t matter,” he said. “I don’t need to know. All you need to know is that I am covering your backs while you are gone. You have shell phones?”

  Aaron pulled his out of his pocket. “Yup,” he said.

  I looked down and didn’t say anything. I still hadn’t told Aaron I’d given mine to Shona. But as long as we had his, we’d be OK.

  “I have one also,” Mr. Beeston said. “A blue one. Call me if you need me. I will do whatever I can to help.”

  I could hardly believe I was thinking it, but for the first time in my life, I was glad to have Mr. Beeston around. “Thank you,” I said.

  He smiled his wonky smile at me, and then he went on. “The small boat will take you along the fjord.”

  “What’s a ford?” I asked.

  “Fjord, not ford,” Mr. Beeston corrected me. “Say it as if it’s spelled ‘fyord.’”

  “Fjord, then,” I said. “What’s one of those?”

  “It’s a narrow stretch of water, like a thin river. They are all over the place here, weaving in between the mountains and linking the lakes to the sea. After the boat drops you off at the end of the fjord, you’ll catch the funicular train to the top of the mountains. You’ll get the best views of the glacier from there, and hopefully you’ll see where you need to go next.”

  “Thank you,” Aaron said.

  “You know that the water here will be unbelievably cold. I presume Neptune has prepared you for this?”

  I felt inside my pocket and closed my hand around the bottle Neptune had given us. “We’re prepared,” I said.

  “And have you got any provisions?”

  “I’ve got a couple of rolls and some fruit from the lunch buffet,” Aaron said.

  “And I’ve brought a bottle of water,” I added.

  “Right, then,” Mr. Beeston said, standing to attention so suddenly that I almost thought he was going to salute us. Instead, he reached out a hand. For a moment, he looked as if he were going to shake our hands. Perhaps suddenly remembering that we were kids and not an elite and highly trained team of secret agents, he changed his mind and patted us both awkwardly on our arms.

  “Neptune knows what he’s doing,” he said. “You’ll be fine.”

  I wasn’t sure if I believed him on either of those statements, but as a large door opened on the side of the cruise ship and a smaller boat pulled alongside, I decided I would make his statements my mantra: Neptune knows what he’s doing. We’ll be fine.

  If I repeated it over and over in my mind often enough, I might even end up believing it myself.

  The small boat glided elegantly along the icy waters of the fjord: a river so tiny and so twisting it felt as if we were sailing through a hairline crack in the world. On either side, enormous mountains rose up into a perfect blue sky. Each of them was covered with a smattering of snow at the top and alternating rocky drops and deep-green forests down their sides.

  Here and there, a waterfall ran through a crack between the mountains, gushing down and forking out at the bottom to spill into the water below. Next to these majestic mountains, even our huge ship looked tiny. I’d never seen anything like it, and for a moment I forgot what we were here for and let myself enjoy the view.

  “Ready?” Aaron nudged me and pointed to a jetty ahead of us. Behind it, a steep pair of tracks and a wire above them led all the way up one of the mountains. “Looks like this is our stop.”

  The boat pulled up alongside the jetty and we all piled off and into the carriage that was waiting to take us up the mountain. Aaron and I sat near the front, gradually watching the world below us grow smaller and farther away. We could see our boat in the distance; it looked like a toy. As the view of the fjords opened up, they looked like a giant’s fingers stretching out across the land, reaching into crevices and cracks and tiny
, winding hiding places.

  Around us, people mingled and shuffled about, pushing past one another to take photos of the view. We sat, squashed tightly together, fingers entwined just as tightly, saying nothing.

  At the top, everyone piled out of the carriage and dashed over to the viewing platform. We held back before making our way over to the other side of the summit.

  Once we got there, the sight made me gasp. A stretch of water — another fjord — separated us from the range of mountains a short way away. The mountains looked as if they were set in a ring. The far one was covered in a glacier that looked like a giant’s tongue reaching all the way down the mountain, as though stretching out to take a lick from something — presumably a lake — down below. We couldn’t see the lake itself from here, but we could see enough to know that this was the place Neptune had told us to find, and that the lake would be exactly where Neptune had said: in the center of the mountains.

  If I’d had any doubts about whether his dreams really were memories, they disappeared now, as I looked across at the glacier. I turned to Aaron. “How are we going to get there?”

  “We’ll have to take one of the paths down this mountain first, then swim across the fjord. Maybe we’ll find a break in the ring of mountains somewhere and get to the lake.”

  “And if we don’t?”

  “If we don’t, I guess we’ll have to try to climb over the top of one of the mountains. But we can worry about that when we get there.”

  I nodded. We weren’t exactly overwhelmed with options.

  I looked around to see if anyone was watching us. Thankfully, they were all far too busy standing at the edge of the viewing platform taking photos of one another to notice us.

  “Let’s go,” Aaron said.

  We edged away from the groups still squealing and pointing, and made our way to the edge of the summit. The path down looked straightforward enough — apart from the bottom part. From here, it looked as though the path ended a long way off the water. We’d probably have to jump the last bit.

  As we picked our way down the rocky path, I prayed that Neptune’s potion would work once we got into the sea. If it didn’t, we’d both be dead from hypothermia in a matter of minutes.