It was a good question and one she sought answers to herself. “If there are life forms.” Cate exhaled slowly. “Well, maybe there was an opening to the ocean a long way back. The creatures entered, and then an earth movement sealed them all in and cut them off from the outside world. Many times in the past, the ocean levels were much higher than they were today. Pretty much all of the coast, from Alaska down to California was submerged for twenty to fifty miles inland. It was nothing but shallow seas and coastal swamps. When the water receded, maybe some of the deeper pockets remained, and then somehow became landlocked.” She shrugged. “It’s one theory.”

“But living in darkness?” Dmitry tilted his head. “I know of cave lakes in Ural Mountains; but things there are little.” He made his finger inch along in front of her.

Cate remembered the image of the tooth – Jack had said it was hard to judge size. Somehow, she didn’t think it was some sort of tiny blind eel down in those depths. She looked back to Dmitry. “Well, that’s what we hope to find out.” She spun back to her console, gripping it again as she heard a metallic clunk, the groan of steel and then the submersible swung slightly in its cradle.

Jack put a hand to his head, pressing the microphone cup in tighter for a second or two, before turning in his seat.

“Get ready, ladies and gentlemen, the drop is about to commence. Next stop Seatopia.”

“Seatopia?” Greg chuckled. “I like it.”

Abby stopped making notes for a moment, and turned to Cate, grimacing. “I’m nervous.” She held up a hand; it shook slightly.

Cate wanted to hug the younger woman, but held up her own hand. The fingers also trembled. “I wouldn’t worry about it if I was you.”

There came a jolt, and then nothing. Cate knew the crane was now lowering the vessel. They would descend at about four miles per hour – little more than walking speed. It would take a full hour to drop all the way down to the inky black sea, where the hydraulics would slow, easing them gently into the water like an old man easing into a hot bath. It was then up to Dmitry to climb up and detach the tethers that would remain dangling in place. They’d all get to say one last goodbye and then they’d submerge and head east towards the vast body of the underground sea.