Ben quickly closed the distance to the plateau so that the sub’s starboard tailfin was within six feet of the rock face. Keeping our speed at fifteen knots, he ascended the Barracuda steadily from its eight-hundred-foot depth, his voice grumbling in our headphones. “I took this mission hoping to find fifteen-million-year-old mollusks, not thirty-foot lake carnivores.”

“The thirty-footer is a vegan. It’s the second creature we have to worry about.” My eyes remained focused on the second blip on the monitor, still rising beneath us.

Ben would not let up. “You’re assuming it’s a predator. Tell me why.”

“It moves like a carnivore. I think it’s been stalking us. It’s also fifty to sixty feet long, which renders it a threat.”

“Another eel?”

“No, Ming. Eels prefer the cold. This creature was warming itself in the vent field like a reptile raising its body heat in the sun.”

Ben veered us away from an outcropping of rock. “Bastard, you know what this is. He knows, Ming.”

I ignored him, my attention focused on the second blip, which had suddenly increased its speed. “It’s making its run. Okay, the first blip is grazing beneath the surface about a thousand feet to the west. Ben, you need to circle it without spooking it.”

“What the hell for?”

“There’s an old saying: when a hungry bear chases you through the woods, you don’t need to be faster than the bear to survive—”

“—you just have to be faster than the next guy. Doc, I like the way you think.” Ben accelerated after the first blip as the second blip accelerated after us.

We were two hundred feet below the surface, kelp whipping past our acrylic glass dome, when we heard a distinct cry over sonar.

“What the hell was that?”

“That, Ben, was the other guy. Come to course three-zero-three. Range to target is 260 feet.”

He accelerated.

Three minutes later we sighted the first blip. It was moving through kelp ninety feet below the algae-covered surface. An adult female, she was thirty-two feet from her snout to her whale-like fluke, her bulbous body weighing well over ten tons. Her calf was a third her girth, its bulk partially obscured in a cloud of its own blood.

“It appears to be a giant manatee.”

“Same family, Ming. Essentially, it really is a Miocene species of sea cow.”

“Look at those sharks circling below. All that blood in the water is like a dinner bell.”

“The mother is trying to push her calf back to the ridge.”

“She’ll never make it,” I muttered.