"From 65 million years ago?"

"Why not? The coelacanth was believed extinct for 300 million years, yet we discovered them to be alive, inhabiting the deep waters off the coast of Madagascar. And Loch Ness is deeper than that."

Several passengers clapped in agreement.

"Okay, but you're comparing a forty-foot reptile with a six-foot-long species of lobe-finned fish."

"What about this!" The German woman, Bibi, held up a copy of a photo she had purchased in Drumnadrochit. It was the famous "surgeon's photo," a surface shot of a long-necked animal resembling a breaching plesiosaur taken by an English gynecologist, R. K. Wilson, back in 1934.

"Sorry, Bibi, the photo's a fake. The photographer claimed the animal had been several hundred yards from shore when he shot it. An analysis of the angle of the shot and its ripples, completed decades later, proves the photographer was only about thirty yards away. The man who took it actually confessed to using a miniature model before he died."

"Attention! attention!" Brandy interrupted, "we're approaching Eileen Mhuireach, or Murdoch's Island, sometimes called Cherry Island. This island, the only one on Loch Ness, is actually a manmade structure known as a crannog. It was built back in the sixteenth century as a fortified retreat. This particular crannog is made of a raft of oak logs and heavy rocks. The whole thing's secured to the bottom using a series of wooden posts."

The passengers hardly glanced at the man-made island, their attention still focused on me.

A stocky American rose from the far end of the bench, and I recognized his wrestler's physique, which was covered in tattoos. "We met years ago, Dr. Wallace. Chris Oldham?"

"Yes. You were one of the assistant producers who worked on that NOVA special."

"That's right. 'The Beast of Loch Ness', the one that aired back in '99. Our show reunited researchers Charlie Wyckoff and Bob Rine. Anyway, if you recall, despite having access to modern sonar equipment and high-tech underwater cameras, nothing conclusive ever came out of our investigation."

"Just like all the other investigations that preceded it."

"Exactly. Now you began this little boat ride stating you felt certain something large inhabits this Loch—those were your very words. Coming from the only person ever to witness a living giant squid, well, let's just say I take your claim rather seriously. Still, everything you've said since then flies in the face of that statement."

A telltale purple spot winked at me in the corner of my right eye.

"You've eloquently told us everything the monster is not. How about telling us what you think the monster really is."

Murmurs of agreement. The passengers pushed in closer to listen. "Maybe I should clarify my earlier statement. It was just a personal belief, nothing more."

"Based upon what body of evidence?"