I swam out from under the rock. "What are you doing here?"

"Emily!" He swam over toward me. "Why have you run away?"

I retreated farther under the rocks. "I've let you down. You, Mom, everyone. We'll get thrown off the island and it's all my fault. I'm so sorry."

Dad squeezed into the creva.s.se with me, scattering clouds of sand as he slithered along the rock. "No one's going to throw you off the island, little 'un. Why would they do that?"

"You don't know!" I wailed. "You don't know what I've done." A tear snaked down my cheek, mingling with the water. All this time! All those years without him, and now that I'd found him, I'd done something so stupid, so awful, he'd hate me forever. I'd ruined everything.

"What? What have you done?"

I bit hard on my lip, squeezing my eyes shut.

"Whatever it is, you can tell me. We'll figure out what to do together."

My face was wet with tears. "It was me!" I blurted out. "I woke the kraken!"

"You what? But how -"

"I went exploring! I knew I shouldn't have, but I did. It was in a cave. I'm so stupid! I found it. I woke it up, Dad. I've ruined everything. I'll never be able to show my face on the island again. You've only just got out of prison and now - oh, Dad, I'm sorry."

Dad stroked my face. "Look. I don't quite understand, but it'll be okay. We'll fix this. I'll look after you."

I pushed his hand away. "Dad, it won't be okay. Don't lie to me. I'm not a baby!"

He stared at me, his face red as though I'd hit him. As I held his gaze, he nodded slowly, as though he was watching me grow up in front of his eyes, catching up with who I really was, instead of who he remembered me being. "You're right," he said eventually. "Of course you're not." He turned to swim away.

"Wait." I grabbed his arm. "I'm sorry."

"You know what you are?" he asked, his voice as tight as his mouth.

I shook my head, holding back fresh tears.

"You're my daughter, that's what you are. You're a Windsnap. And you know what that means?" Before I had a chance to answer, he added, "It means we're going to straighten this out."

"I'm not going back to the meeting. I can't. Please."

"Who said anything about going back there?"

"What, then?"

Dad stopped swimming and searched my face. "We're going to the cave. Show me where it happened."

"The kraken's cave?"

"Why not? You heard what Neptune said. It's probably still in there. Maybe we can straighten this mess out, somehow. Seal it back up so it's safe again or something."

"Dad, it was really frightening. It was the most terrifying thing ever!"

"Worse than going back to face Neptune? You stood up to him in his own court, remember."

I dropped my head. "I know. That was pretty frightening, too."

"Exactly. And you did that, so you can handle this as well."

"I suppose."

"Come on." He held out his hand. "Let's see what we can do."

Letting out a breath it felt as if I'd been holding in for a week, I took his hand and we swam on.

"It's that way," I said as we came to the lagoon. It looked different. The water was murky and muddier than I remembered. Sand-colored flatfish skimmed over the seabed, moving beneath us like shifting ground.

My throat closed up. We'd reached the carving on the wall. The trident. How on earth could we have missed it last time? Maybe if we'd seen it, none of this would have happened.

It was pointless thinking like that.

We came to the pinwheel, except this time when I looked at it, I realized I knew exactly what it was. The long shoots spiraling out from the round body in the center . . .

"That's it," I said, my voice rippling like a breaking wave. "I don't want to go any farther."

He stopped swimming. "We need to do this, little 'un - I mean, Emily."

"Dad, you know, it's okay if you want to call me -"

"No." He put a finger over my lips. In charge. Strong. "You're not a baby. You're a scale off the old tail, and I couldn't be more proud of you. And we're going to get to the bottom of this, find out what we can, right?"

"But it's out of bounds. This was how the whole trouble started."

"And this is how it'll end, too," he said. "You don't think we found ourselves at this place by the pair of us doing what we were told, do you?"

I didn't say anything.

He reached out for my hand. "Come on. I'll go ahead, but you need to tell me where I'm going. I'll look after you."

Eventually, I took his hand and we swam in silence.

Everything looked familiar, until we came to an enormous gash in the rock. Maybe the size of a house.

"In there." I held out a shaky arm. "Except it was a tiny hole last time!"

Dad swallowed. "Okay, then. You ready?"

"I'll never be ready to go back in there." A solitary fish flashed past me: soft green on one side, bright blue on the other, its see-through fins stretched back as it swam away from the cave. Sensible fish.

"Come on. You'll be okay. I'm right beside you." He squeezed my hand and we edged inside, slipping back through the rock.

But it was completely different. So different that I started to wonder if we were in the wrong place. There were no thin winding channels, just huge gaping chasms all the way. We swam through them all.

And then we came to the gold. We were in the right place. Jewels and crystals lay scattered across the seabed. As we swam lower, the surroundings felt less familiar. Colder. And there was something else. Something very different. The deeper we got, the more we saw of them.

Bones.

Just a few at first, that could perhaps have pa.s.sed for driftwood. Then more: clumps of them, piled up like the remains of a huge banquet. Long thin bones, twisty fat ones - and then a skull, lying on the sea floor. A dark fish slipped through an eye socket. I clapped a hand across my mouth.

"Dad!" I gripped his hand so hard I felt his knuckles crack.

"Don't look at them," he said, his voice wobbling. "Just stay close to me."

We swam into every bit of the cave. Every inch.

"What do you see?" Dad asked as we paused in the center of the biggest chasm.

I looked around. "Nothing."

"Exactly." He turned to face me, suddenly not in charge anymore. Not strong. Just scared. "It's gone, Emily. The kraken - it's on the loose."

How long have we been here? A couple of days? Who knows? All I know is we're stranded on a deserted sc.r.a.p of an island, the boat's broken, and I'm hungry.

And scared.

Nuts! How long can a person live on nuts? And water from an iffy-looking stream. Dad figures he'll catch us some fish. And he thinks we could fix the boat if we all "shaped up a little." He's acting as if he's on some kind of Boy Scout trip, as if this is all part of the adventure. I know he's putting it on, though. It's too manic. I can see the truth in his eyes. He's just as scared as I am.

Mom's hardly spoken. It's best that way. If we talked more, we might end up talking about what happened. About how we could have died. About the . . .

Anyway.

It's hardly even an island. I can vaguely see something that might be a real island, out at sea. Far too far to swim. Just our luck to get stranded on this tiny speck of land instead. Two hundred paces from one side to the other. I counted yesterday. Or the day before, I don't remember. Some time when I was collecting twigs so that Dad could build us a so-called shelter. Not that I'm likely to get any sleep. It lends itself to a touch of insomnia, getting stranded on an island the size of a pair of underpants, with nothing to eat, no way of getting home, and no one to talk to except your parents.

Not even the captain.

That's another thing we don't talk about. I try not to think about that, either. What happened to him? Could he be - My hands start to shake uncontrollably. My legs feel as if they'll give way any second now. Like I said, best not to think about that.

There's a splashing noise behind me.

"Mandy! Where's your mom?" It's Dad, coming out of the water with one of the nets from the boat. He's wearing purple shorts down to his knees and he's waddling onto sh.o.r.e in his flippers. He's been off looking for fish. That's all he's done since we've been here. That and mess around banging and hammering on the boat. It's washed up on the tiny beach, half-filled with water and littered with sh.e.l.ls and stones and broken bottles. Yeah, sure, Dad. It's going to be so easy to fix.

The net's empty, as usual.

Dad pulls his mask and snorkel off. He's grinning. What on earth can he find to smile about? Doesn't he realize we're stranded and we're all going to die? Maybe he got knocked on the head when the boat went under.

He's shaking himself dry. "Come with me. I've got something important to tell you both."

I follow him back to the pathetic bundle of twigs that seems to have become our home. Mom's sitting on the ground leaning against a palm tree. She's not doing anything, just staring into s.p.a.ce. Her hair's sticking out everywhere, as though she's had an electric shock. Her face is white, her eyes unfocused. She looks like a madwoman.

"Maureen, Mandy - our problems are over!" Dad announces.

I can't help it; I burst out laughing. I mean, look around you, Dad - wake up and smell the coffee. Oh, sorry, I forgot. THERE ISN'T ANY COFFEE BECAUSE WE'RE MAROONED ON A STRIP OF LAND YOU COULD MISS IF YOU BLINKED, WITH NOTHING BUT NUTS, INSECTS, AND A SMASHED-UP BOAT FOR COMPANY!

"Just hear me out," Dad says. "You're not going to believe me, but I swear, every word is true." There's a tic beating against his red cheek. "I swear," he repeats.

Mom sighs. "Just tell us. What ridiculous idea have you come up with now?"

"It's not an idea, Mo. Well, not exactly. It's something I've seen."

Mom raises her head a fraction. "What have you seen, then?"

Dad puffs out his chest and looks from one of us to the other. "Mermaids." I watch the lump in his throat bob up and down. "I've seen mermaids."

"Oh, for heaven's sake, Jack!" Mom pulls herself up and shakes out her skirt. "When are you going to act like a proper man and fix this mess, rather than indulging your stupid fantasies?"

She starts to walk off, wiping sand off the backs of her legs. Dad grabs her arm. "It is not a fantasy, Maureen!" he says furiously. "I swear on every breath I've ever taken, there are mermaids! Not here, farther out. I've seen them swimming, under the water. They've got tails - long, glistening, shiny tails!"

Their eyes are locked. It's as if they're acting out some surreal sketch and the teacher has just said "Okay, freeze, everybody!"

But there's something about what he's said; something just out of reach . . .

"Don't you understand what this means?" Dad says. His neck's bright red and bulging. He's gripping Mom's arm.

Mom stares at him. "No, Jack. I'm afraid I don't know what it means at all. That you're cracking up, perhaps? Well - don't worry, I'm sure I won't be far behind you." She pulls out of his grip.

"Mo, I'm not cracking up!" he shouts. "You've got to believe me! We could save our home, the amus.e.m.e.nt arcade - the whole pier!" He turns to me, his eyes wild and intense. "Mandy, you believe me, don't you?"

"I -" Of course I don't believe him. Of course I don't! But there's something. Something. What is it?

Mom's shaking her head. "You'll forgive me if I don't quite follow your logic."

Dad holds up his net. "We capture one! Take it back to Brightport. We can have it on show, charge admission and everything. We'll take care of it, of course. Give it a good life. People will travel from all over the country to see it! From all over the world, maybe! We'll be heroes in the town; we'll pay for the pier to be renovated. Don't you see? This could solve all our problems!"

Mom sucks in her cheeks. "Jack," she says, "you haven't managed to catch so much as a goldfish since we got here! Even if I were to believe that you have seen a mermaid - which, frankly, I don't - how in heaven do you propose to catch the thing?"

Dad pulls at his net. "I haven't got the whole plan figured out yet, have I? I've only just seen them. A group of them. Swimming in the deep water. One of them had gold stars shining in her tail. There was a merman too, with long black hair and a shiny silver tail. A merman! For G.o.d's sake, Maureen!" He grips her arm again. "I'm telling the truth! You'll see I am."

Mom pulls away and turns to me. "Come on, Mandy. Help me get some dinner. I've had enough of your father and his daydreams for one afternoon."

I follow Mom as we pick our way through undergrowth, scavenging for food like vagrants. As usual, we don't talk. But this time, it's because of the thoughts going around in my head, thoughts I'm not sure I dare share with Mom. There's definitely something familiar about what Dad said. Something niggling away in the back of my mind. I can't put my finger on it.

Maybe it's something I've seen on TV. A film about mermaids or something. I've got this picture in my mind. Someone swimming. She's got a tail and she's spinning around, smiling, grinning - at me! She's in a pool. It's not from TV. I'm sure it isn't. It feels real. It feels like a memory.

I grab a couple of nuts and shove them hard into my pocket. Mermaids! As if! I force myself to laugh.

We'd better get away from here before we all crack up.

"Dad."

He didn't reply. Just kept on staring out to sea. We'd spent half the day swimming around the coast, trying to keep out of sight, and trying to figure out what to do next. We stopped to rest at a large rocky bay on the east side of the island, just a little farther down from our bay.

I swam over to join him next to a huge boulder at the edge of the bay. "Dad," I said again.