"Double Arch Bay," Althea said.

Ahead of us, two giant arches were cut deep into the rocky sh.o.r.e. Althea ducked under to swim through one of them. Shona went next. Then I flicked myself down and slipped through.

We swam across a small reef. Neat cl.u.s.ters of plants and coral were dotted about, making it like a well-tended park. An elderly merman with shiny blue eyes and a thin gray tail swam across them, snipping at weeds with a knife made from razor sh.e.l.ls.

"Hi, Theo," Althea said.

He nodded at us. "Morning, girls."

"Theo's the gardener," Althea explained as he swam off to tie some wilting pink plants into a bundle with seaweed.

There were archways everywhere. Some were tiny gaps in the rocks that I'd have missed if Althea hadn't pointed them out, others wide jagged holes big enough for a whale to get through.

Eventually, we came to a shimmery purple rock with a neat round hole in the middle. "This is where Marina lives," Althea said. She tapped a pink fish hovering at the entrance, a gold bell dangling from its tail. Immediately, it wriggled its body and a delicate sound chimed.

A mermaid swam toward us from inside. She had curly red hair and a long gold tail with a shiny crescent moon painted on the end. "You must be Shona and Emily!" she said, her freckled face creasing into a smile. "Come in while I get my things." She grabbed Althea's hand and they went on ahead, along a narrow pathway lined with rough walls. It soon widened out into a wide living s.p.a.ce divided up by trails of fern and kelp. An older mermaid bustled past us. She had red hair like Marina's, only hers was longer and frizzy. Her tail was bright yellow and tapered into soft white ta.s.sels at the end.

"Don't be out all day, Marina," she said. "It's jellied eel souffle tonight and we're eating early. I've got my synchro swim cla.s.s at seven." Then she smiled at Shona and me. "h.e.l.lo, girls," she added. "Welcome to Allpoints Island."

Shona and I smiled back before following the others into a small s.p.a.ce with a soft seaweed bed and drapes all around it. A huge pink sponge was squashed into one corner, a crystal mirror in another.

"My room," Marina said.

I sat on the sponge. It squelched and bubbled under me. Shona laughed. "It's swishy!"

Swishy - that's Shona's word for everything she likes. "Squishy, more like," I said as I tried to get up.

Althea swam toward the entrance. "Come on," she said. "There's loads to show you."

Marina grabbed a patchwork bag made of leaves and reeds and followed Althea, with Shona close behind. I fumbled my way out of the sponge and caught up with them as they slithered through the arches and back out into the bay. We swam along stretches of rocky coastline, interspersed with coves of all shapes and sizes: some wide and sandy, others tiny winding channels you could almost miss.

Everywhere we looked, spots of sunlight bounced on the water, white foamy waves washed gently over rocks, and palm trees reached gently out from marshmallow sand. High on the island, some people called down to us from a woody hill. In the sea, merfolk smiled and greeted us as we pa.s.sed them. A couple of young mer-children riding piggyback on a dolphin waved and shouted to us. We waved back. A group of mermen diving for food nodded at us on their way out to sea. A mermaid with long flowing hair streaming down her back smiled as she was pulled along by a swordfish on a leash.

It was all so different - and yet so familiar. I belonged here. The fear that had gripped me since yesterday floated further away with every new sight.

Swimming on, we approached a half-hidden cave in the rocky sh.o.r.eline. "There are loads of caves on the island, but we only use a couple of them," Marina said. "School's in one of them. The other's only for really major events, like when Neptune comes. That's the Grand Caves. We can show you the other one, though, Emerald Caves. You want to see your school?"

Did I? Just the thought of school washed the smile off my face. But surely this couldn't be anything like Brightport Junior High. No one was going to make fun of me here or delight in making my life a misery. And it was a mermaid school! A mix of emotions and questions swirled around inside me as I followed Althea into the cave. It wouldn't happen again, would it? It couldn't; I'd make sure of it. I'd do everything I could to show the mermaids I was just like them.

We inched along a narrow tunnel. As it twisted and turned, it grew darker and darker. Soon we were swimming in pitch-blackness.

"Feel your way along the walls," Marina called from somewhere ahead of me. I ran my fingers along the craggy layered sides as I edged down the tunnel.

Just as my eyes were getting used to the dark, the tunnel opened out and grew lighter. We came to a fork.

"Down here." Marina pointed along a tunnel that shimmered with green light.

It led up into a deep pool inside the cave. Above us, the ceiling stretched high and jagged. Stalact.i.tes hung all around us: enormous pillars reaching almost to the water, tiny spindles spiking down like darts. Rocks glimmered and shone purple and blue and red. Next to the pool, smooth boulders were dotted about on the gravelly ground like an abandoned game of giants' marbles.

A long scroll hung from the ceiling, pictures of underwater life drawn all over it, a pile of different-colored reeds underneath.

A young mermaid was cleaning some hairbrushes lined up on a rocky ledge that jutted across the water. She smiled at us as we gazed around.

"Swishy!" Shona said, swimming over to the hairbrushes. "You have Beauty and Deportment?"

Beauty and Deportment. Shona had told me all about that. I'd be studying it with her soon. And Diving and Dance, and all the other mermaid subjects. No more long division!

"Of course," Marina smiled. "It's my favorite subject."

"Mine, too," Shona breathed.

Althea looked at me. "I prefer Shipwreck Studies."

I tried to think of something to say, to join in the conversation. But it was all so new and alien to me. They'd all been studying these subjects for years. What if I was no good at them?

"Althea likes going out on Geography Reef Trips," Marina said with a laugh. "Anything to get out of doing her tides tables."

"It's beautiful," Shona whispered as we took it all in. "Much better than my old school."

"And about a million light years away from mine," I added, trying not to think too hard about Brightport Junior High.

"There are two cla.s.ses," Althea explained. "This one's for the older kids. There's another one for the babies."

"Two cla.s.ses?" Shona asked. "Is that all?"

"There's only about thirty families here altogether," Marina said. "Mostly mer-families and a few human ones."

"Do they mix?" I asked. I realized I was holding my breath while I waited for the reply.

"Yes, of course," Althea said as she started swimming back out of the cave. "But they're kind of separate, too." She blushed. "If you get what I mean." She glanced quickly at my tail. I got what she meant. I was the only one. Still the odd one out.

The old fears resurfaced, hitting me like a punch in my stomach. I couldn't keep them away any longer. I'd never find a place where I could fit in.

"But everyone gets along really well," Marina said quickly, swimming across to touch my arm. "And we're all really pleased you've joined us. The island's organizing a party for you next week, once you've settled in."

"We haven't had any new families here for ages," Althea added. "Come on, let's show you the rest of the island."

They were organizing a party, just for us? Maybe I was wrong. Maybe things would work out, after all.

We continued around the coast, Althea and Marina pointing out sights all along the way: a hole in the ground that spouted orange flames in the summer, little channels leading to a maze of caves and caverns where some of the merfolk ran craft stalls. I made a mental note to tell Dad about that. At least it could be something for us to talk about. He'd learned to make jewelry while he was in prison. Maybe he could get one of the stalls.

Swimming up the jagged east side of the island, we came to a channel leading into the rock.

"Now this is something you must see," Althea said.

We set off in single file along the channel. The sides became steeper and higher as we swam; the water grew deeper and colder, and so dark it was almost black. A soft wind whistled through the chasm. Then nothing. No movement, no sound, the sun beating silently down. I'd never experienced such stillness. It felt as though it was inside me, as though it was part of me. For a moment, there was nothing except me and the stillness, silently winding through my body like a snake. Was it a pleasant feeling? I couldn't even tell.

I shivered and shook myself. The others had swum ahead - again. I tried not to show them how tired it was making me to keep up. And I decided not to mention the weird snakelike feeling either. Somehow I didn't think it would help me come across as normal.

As we wound our way along the channel, Althea and Marina kept pointing things out in our path: a fossil on the canyon wall, hairline cracks in the rocks making tiny channels that split off from the main one.

"Look." Althea pointed ahead, to where the channel seemed to come to an end. I couldn't see anything at first, just a lot of overgrown bushes and reeds lining the walls. Then I noticed what she was pointing at. A gap in the rock, through the reeds. There were pieces of driftwood attached to either side of the gap, covered in plants and algae.

We parted the reeds as though they were curtains and peered through the gap in the rock. On the other side, a shimmering blue lagoon sparkled with diamond glints. The water lay virtually still; green ferns hung down across gaping holes in the rock; a group of flamingos gathered at the edge, standing motionless on spindly legs, their long pink necks stretched straight and high. Two pelicans flew past, their wings reaching wide as they skimmed the water's still surface.

It was like paradise. How you've always imagined paradise would look.

"Swishy!" breathed Shona.

I stared so hard my eyes watered.

Marina looked nervous. "Come on. We need to get back."

"But we just got here," I said.

"We shouldn't be here at all."

"We're not really supposed to," Althea said, swimming closer and lowering her voice. "But you don't know that. You could go in and find out what it's like. I've always wanted to know."

I stared at the lagoon.

"I'm not sure," Shona said. "I mean, if we're not allowed . . ."

"None of the kids is brave enough. We've been told not to go in there so many times," Althea said. "But you haven't. You've only been here five minutes! Who's going to tell you off?"

"She's right," I said.

Althea smiled at me. "Exactly," she said.

This could be just what I needed! My chance to make sure Althea and Marina would definitely accept me. If I did this, they'd have to see me as one of them. That was it, I'd decided. I was going to do it. I wasn't going to be whispered about and made fun of again. And I wasn't going to be the odd one out. This was my chance to make sure of it.

Besides, it looked so tempting in there. I could almost feel it inviting me in, beckoning me in, almost pulling me. What was it? Was I imagining that, too?

Shona edged away from the reeds, her tail fluttering nervously. "Let's think about it," she said.

We dropped the reeds and drew back, but I couldn't get the image out of my mind. The stillness of the water, the ferns hanging down like delicate chains. And more than that, the chance to seal my place as one of the mermaids. I had to do it - but I wasn't brave enough to do it on my own. I would have to persuade Shona.

We set off in silence. All around us, nature bustled. Tiny brown lizards raced across rocks. Crabs scuttled under large stones, sneaking into the safety of their hidden homes. Above us, white birds with long sharp tails pecked at the cliff, disappearing into invisible holes in the rock. Eventually, the channel's walls widened once more and the sun warmed our necks as we arrived back at the open ocean.

When the others left us, Shona came to North Bay with me. I grabbed her before we went into the boat. "We've got to go back," I said.

"Oh, Emily, I don't know," Shona said. "I mean, we've only just gotten here."

"That's the whole point!" I said. "Like Althea said, we're new, we don't know our way around, it would be easy for us to get lost. Think how impressed they'll be. Please!"

Shona half smiled. "It did look amazing," she murmured. "And I suppose we haven't really had long enough to properly understand the rules yet."

"Not long enough at all," I said, my tail flicking with excitement, and something more than that. A need, almost a hunger. "We're just having a look around our new home. We're curious, we're a little vague about directions, and - whoops - we've gone the wrong way. No one will be upset with us."

I'm the first one to the door when the mail arrives. I flip through the pile: just more bills for Mom and Dad to argue about.

But there's something else. A letter in a shimmery pink envelope. I turn it over. Mermaid Tours!

"Mom! Dad!"

They're at the door in seconds.

"Oh, my G.o.d!" Mom says, s.n.a.t.c.hing the letter from me. "Who's going to open it?" Her hands are shaking.

"You do it, love," Dad says. "You entered the contest." He holds my hands. I'm shaking, too.

"It's probably just some junk mail or something," Mom says, tearing at the envelope. "Let's not get excited."

She reads aloud. "*Thank you for entering our contest. We are delighted to inform you that you have won our -' Jack!" Mom drops the letter and stares at Dad.

I pick the letter up and read on. "*. . . delighted to inform you that you have won our Bermuda-and-the-Caribbean cruise vacation. You and your family will spend two weeks aboard one of our luxury ships and experience all the delights of a Mermaid Tours vacation. Many congratulations and have a good trip!'"

For a second, there's silence. Then Mom grabs me and screams. She pulls me into a tight squeeze. She's jumping up and down. "We won! We won!" she yells. "We're going on vacation! Oh, my G.o.d, we won, we won!"

I jump up and down with her till I can hardly breathe. She's holding me too tight. I pull away. Mom grabs Dad around the neck and kisses him. Kisses him! I don't think she's done that for about five years.

It worked. She won us a vacation! Maybe they'll start getting along again and everything will be all right. For a couple of weeks, at least.

Wonder if anyone will notice I'm gone. Julia might. She's kind of my best friend, not that she acts like it. She never really wanted to be my best friend. She always preferred that Emily Windsnap. I was just someone to fall back on when Emily wasn't around. Julia was really upset that day when Emily didn't show up. What am I supposed to do? Turn my back on her? Well, Emily wasn't there and I was. So Julia and I are best friends now. Fair's fair.

I wonder what happened to Emily and her mom. It feels kind of weird without them. Not that I miss her or anything. No way. Just that, well, it's kind of quiet around here without her. Sometimes I find myself looking out to sea, wondering if they'll ever come back. Stupid, huh? I'm not saying I want them to, don't get me wrong. Just, I don't know, maybe it could have been different. I mean, if she hadn't gotten me into trouble last year when she told on me for cheating in the arcade, then I wouldn't have had to hate her. I wasn't even cheating; I was trying to help her. Trying to be nice. Taught me not to bother trying that again in a hurry. It never works. Better just to keep your mouth shut and not get your hopes up.

Anyway, we're out of here. We're going on a cruise!

We swam side by side to begin with. Below us, occasional shoals of parrotfish and bright red snappers swept across the sandy bed. When the channel narrowed, I swam ahead, slinking along the silent pa.s.sageway. The ground soon became uncluttered: clear golden sand beneath us, the sun shining down, almost directly above our heads. Two silhouetted mermaid figures gliding along below the surface, our shadows came and went, appearing briefly before suddenly growing distorted with the splash of a tail breaking the water's still surface.

We came to the curtain of reeds draped down the channel's walls and the algae-coated wooden plaques. That's when the feeling started inside me. I didn't know what it was. A quivery kind of sensation jiggling around in my stomach. Nervous. Waiting for something - and a feeling that there was something waiting for me, too. Trying not to let Shona see my quivering hands, I parted the curtain and looked through the hole in the wall. The water sparkled and fanned out into a wide lagoon. Ferns hung down over cracks and gaps in the walls. A white tropical bird flew into a hole behind me, its long tail disappearing into the rock. Nothing else moved. Shona stared.

I turned to her. "Ready?" My voice shook.

She broke her gaze to look at me. "Let's just get this over with."

I glanced around to check that no one had followed us, then I squeezed through the gap and swam into the lagoon. The sun burned down, heating my neck and dancing on the water. Its light rippled below us in wavy lines across the sea floor.

As we slid across the stillness, the water grew colder and murkier. When the lagoon narrowed back into a channel, I couldn't see my reflection swimming along below me anymore. The walls lining our trail had lost their hardness. They were like chalk. I stopped and sc.r.a.ped my finger down the side. I made myself focus on the walls, almost flicking a switch to turn off the nagging wordless worry in my mind. Rock crumbled in my hand. The channel walls stretched upward, cold and gray and deserted.

"Emily!" Shona was pointing at something ahead. An engraving on the wall: a perfect circle with a fountain spiraling out from the center. It looked like a pinwheel, full of energy, almost as tall as us. I had this weird feeling I knew the picture, recognized it. Had I seen it in a book? Dreamed about it? What was it?

"Look at this!" Shona had swum ahead while I stared at the engraving.

I joined her in front of some ferns loosely covering a hole in the rock. The hole disappeared below the surface. We dived down. Under the water, it was just big enough to swim into.

"Cool!" I grinned at her. A secret tunnel reaching into the rock! "Shona, we have to see what's in there."