Just why do humpback whales sing? That's the question that has marine behavioral biologist Nate Quinn and his crew poking, charting, recording, and photographing very big, wet, gray marine mammals. Until the extraordinary day when a whale lifts its tail into the air to display a cryptic message spelled out in foot-high letters: Bite me.

Trouble is, Nate's beginning to wonder if he hasn't spent just a little too much time in the sun. 'Cause no one else on his team saw a thing -- not his longtime partner, Clay Demodocus; not their saucy young research assistant; not even the spliff-puffing white-boy Rastaman Kona (né Preston Applebaum). But later, when a roll of film returns from the lab missing the crucial tail shot -- and his research facility is trashed -- Nate realizes something very fishy indeed is going on.

By turns witty, irreverent, fascinating, puzzling, and surprising, Fluke is Christopher Moore at his outrageous best.

Amy called the whale punkin.

He was fifty feet long, wider than a city bus, and weighed eighty thousand pounds. One well-placed slap of his great tail would reduce the boat to fiberglass splinters and its occupants to red stains drifting in the blue Hawaiian waters. Amy leaned over the side of the boat and lowered the hydrophone down on the whale. "Good morning, punkin," she said.

Nathan Quinn shook his head and tried not to upchuck from the cuteness of it, of her, while surreptitiously sneaking a look at her bottom and feeling a little sleazy about it. Science can be complex. Nate was a scientist. Amy was a scientist, too, but she looked fantastic in a pair of khaki hiking shorts, scientifically speaking.

Below, the whale sang on, the boat vibrated with each note. The stainless rail at the bow began to buzz. Nate could feel the deeper notes resonate in his rib cage. The whale was into a section of the song they called the "green" themes, a long series of whoops that sounded like an ambulance driving through pudding. A less trained listener might have thought that the whale was rejoicing, celebrating, shouting howdy to the world to let everyone and everything know that he was alive and feeling good, but Nate was a trained listener, perhaps the most trained listener in the world, and to his expert ears the whale was saying -- Well, he had no idea what in the hell the whale was saying, did he? That's why they were out there floating in that sapphire channel off Maui in a small speedboat, sloshing their breakfasts around at seven in the morning: No one knew why the humpbacks sang. Nate had been listening to them, observing them, photographing them, and poking them with sticks for twenty-five years, and he still had no idea why, exactly, they sang.

"He's into his ribbits," Amy said, identifying a section of the whale's song that usually came right before the animal was about to surface. The scientific term for this noise was "ribbits" because that's what they sounded like. Science can be simple.

Nate peeked over the side and looked at the whale that was suspended head down in the water about fifty feet below them. His flukes and pectoral fins were white and described a crystal-blue chevron in the deep blue water. So still was the great beast that he might have been floating in space, the last beacon of some long-dead space-traveling race -- except that he was making croaky noises that would have sounded more appropriate coming out of a two-inch tree frog than the archaic remnant of a superrace. Nate smiled. He liked ribbits. The whale flicked his tail once and shot out of Nate's field of vision.

"He's coming up," Nate said.

Amy tore off her headphones and picked up the motorized Nikon with the three-hundred-millimeter lens. Nate quickly pulled up the hydrophone, allowing the wet cord to spool into a coil at his feet, then turned to the console and started the engine.

Then they waited.

There was a blast of air from behind them and they both spun around to see the column of water vapor hanging in the air, but it was far, perhaps three hundred meters behind them -- too far away to be their whale. That was the problem with the channel between Maui and Lanai where they worked: There were so many whales that you often had a hard time distinguishing the one you were studying from the hundreds of others. The abundance of animals was a both a blessing and a curse.

"That our guy?" Amy asked. All the singers were guys. As far as they knew anyway. The DNA tests had proven that.

"Nope."

There was another blow to their left, this one much closer. Nate could see the white flukes or blades of his tail under the water, even from a hundred meters away.

Christopher Moore is the author of seven novels, including this one. He began writing at age six and became the oldest known child prodigy when, in his early thirties, he published his first novel. His turn-ons are the ocean, playing the toad lotto, and talking animals on TV. His turn-offs are salmonella, traffic, and rude people. Chris enjoys cheese crackers, acid jazz, and otter scrubbing. He lives in an inaccessible island fortress in the Pacific. You can e-mail him at BSFiends@aol.com. Visit the official Christopher Moore website at www.chrismoore.com.

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