The food coloring didn't show up as brightly in the sea as it did in the store bottles, but you could definitely see it. As Abbey and I had hoped, the current and the wind were in our favor, transporting the dye down the shoreline in a shiny stream from Dusty Muleman's basin.

Dad and Grandpa Bobby stood together on Thunder Beach, admiring the telltale trail of fuchsia.

“I'm impressed,” my father said. “This was your idea, Noah?”

“Abbey's, too,” I said.

“All I did was pick out the color,” she said.

“That's not true. We were fifty-fifty partners the whole way.”

My grandfather slapped a hand on Dad's shoulder. “Paine, you and Donna really lucked out with these youngsters. They're true champs, both of 'em.”

“Most of the time,” Dad said, shooting us a sideways glance.

“You gotta admit,” said Grandpa Bobby, “this is a whole lot neater than sinkin' the man's boat.”

“Yeah, Pop, thanks for bringing that up.”

Mom kept staring at the purplish slick in the shallows. Even though she was wearing sunglasses, we could tell she was upset. At first I thought she was mad at Abbey and me, but it turned out that she wasn't. She was mad at Dusty Muleman.

“Unbelievable!” she exploded finally. “How can a person do something like that! A father, for heaven's sake! All the kids on the island go swimming here-and he's poisoning the place with all this… this…”

“Ca-ca?” said Abbey.

“Whatever,” my mother fumed. “The man ought to be in jail. He's a menace to the public health.”

Dad has a long list of people that he says should be locked up for one thing or another, but this was the first time I'd ever heard Mom say that about anybody.

My grandfather also was angered by what he saw, although he tried not to show it. “Jail's too good for the lowlife who did this,” he said evenly, “but it's a start.”

Abbey and I looked uneasily at each other. We'd seen Grandpa Bobby in action before.

“Paine, you 'member that big muttonfish I caught here?” he asked my father. “The fifteen-pounder?”

“You bet I remember. Only it was fourteen pounds,” Dad said. “Fourteen even.”

“Sure? Anyways, it was a helluva catch,” said Grandpa Bobby. “That was back before they dropped fish traps all over the reefs. Back before certain creeps started dumping their crapola in the sea.”

There was a rumbly edge to his voice, like he was struggling to keep his temper under control.

Mom said, “Don't worry, Pop. Someday Dusty Muleman will get exactly what he deserves. People like him always do.”

This was her famous what-goes-around-comes-around theory. My grandfather obviously didn't buy it, although he was too polite to say so. He picked up a branch of driftwood and swept it back and forth through the stained water.

“Somebody probably oughta notify the Coast Guard, while the tide's right,” he said.

I didn't mention the phone call I'd made earlier at the house. As if on cue, a sound like a rolling drumbeat rose from the north.

Abbey said, “Listen, guys! You hear that?”

Thwock-a-thwock-a-thwock…

We all turned and looked up.

“Over there!” said Dad. He has eyes like an osprey; the rest of us couldn't see a thing.

After a while my grandfather spotted it, too, and pointed where to look. At first it was just a small fuzzy dot in the wide open blueness of the sky. But as the dot grew larger, it turned blaze-orange and took on the shape of a helicopter.

The drumbeat of the rotors became a loud, high-pitched whine as the chopper circled lower. On its belly we could plainly read the words COAST GUARD. A side door rolled open, and a man in a dark jumpsuit leaned out. He was wearing a white crash helmet and aiming a camera down at the water.

Taking video of our amazing fuchsia river.

We waved at the Coast Guard man, but he was too busy to wave back. The helicopter gradually began to move, following the colorful current of evidence all the way up the beach, all the way to the marina where the Coral Queen was moored. There the chopper hovered for a long, long time.

Dusty Muleman was officially busted.

Abbey whooped and Grandpa Bobby clapped and I pumped a fist in the air. We headed home feeling hopeful and happy-though Dad and Mom weren't quite happy enough to forget about me and Abbey sneaking out the night before.

“By the way, you're both grounded,” Mom informed us in the car.

I signaled for Abbey to stay cool, but she ignored me.

“Grounded for how long?” she asked indignantly.

“Indefinitely,” Dad said.

Which was better than setting an exact number of days or weeks. From experience I knew that an “indefinite” grounding could be negotiated favorably-if only Abbey would quit whining.

“It's not fair,” my sister said. “In fact, it really bites.”

“Watch your mouth, young lady,” Mom warned.

“But we just saved Thunder Beach! Don't we get bonus points for that?”

Grandpa Bobby said, “Abbey, darlin', it won't be so bad. Anyways, it's probably a smart idea for you and your brother to lay low for a while.”

And he was the family expert on laying low.

I waited until we got back to the house before asking my parents to delay the starting date of our grounding. “Just until tomorrow,” I said. “Please?”

My father eyed me suspiciously. “Why? You've got big plans for this afternoon?”

“I need to go thank Shelly.”

“Me too,” said Abbey, scooting to my side.

Dad left the decision to Mom, who drilled us with one of her I'm-not-kidding stares. “You've got exactly one hour,” she said. “Not a minute more.”

We dashed for our bikes, Abbey calling over her shoulder, “Grandpa Bobby, you'd better be here when we get back!”

My mother and father honestly care about each other, but they argue about plenty of stuff. Sometimes it seems silly to me and Abbey, but other times it's really heavy. For instance, Mom was ninety-nine percent serious about divorcing Dad if he didn't come home from jail and get his act together. I totally understood why she felt like that, and at the same time I could see the point he was trying to make by sinking the Coral Queen.

But even when my parents are fighting, they don't actually fight. It's only sharp words back and forth; no fists or blunt objects.

Unfortunately, some people really get carried away-as my sister and I were reminded when we showed up at Shelly's trailer.

She was sitting on the steps, gazing off into the distance. She wore black jeans, a gray Gap T-shirt, and a blue trucker's cap turned backward.

In one hand was a sweaty bottle of beer, and in the other hand was a rake. Some of the tines were snapped off, and others were bent at sharp angles. It wasn't the sort of damage caused by normal, everyday gardening.

“What's wrong?” I asked.

“Love is a strange deal, I swear,” she said. “You wanna come in? It's a awful mess, I'll be honest.”

“We'll help you clean up,” Abbey offered.

“What kind of mess?” I asked.

“Like nothin' you ever saw before,” Shelly said. “Think you can handle it?”

After seeing the condition of the rake, I wasn't so sure. To stall I asked her what had happened on the Coral Queen after I'd jumped overboard.

She laughed. “Nobody heard a thing because the band was so loud. Everybody just kept drinkin' and gamblin'. The customers who saw you run past, they figured you belonged to one of the crew.”

“What about that nasty old lady who tried to break into the bathroom?”

“Oh, her? Free stack of chips and she was back at the blackjack table, happy as a clam,” Shelly reported. “Speaking of bathrooms, I had to make, like, seven trips before I got rid of all that purple goo. Every time I'd get settled nice and cozy, somebody'd start bangin' on the door, sayin' they couldn't wait. My wrist hurts from flushin' so much.”