Cate drew in a deep breath, momentarily feeling overwhelmed by the millions of tons of rock pressing down on top of her. She guessed there’d be air pockets along the way that they could surface into if need be, and some of them would be huge dry caverns, perhaps with dark rocky beaches lapping at stygian bays. As the oxygen content of the water was high she had to assume that any air pockets they came across would be breathable. They had more than enough air for the trip, but it might be nice to take a breath of something other than canned air.

Cate closed her eyes, and listened to her heartbeat. In what seemed just another few minutes she felt a settling of weight in her body, and knew that meant they were being eased into the water. She turned and saw Jack listening to a voice high overhead, or perhaps they were sitting back in some comfortable office somewhere.

“Okay Base, we’re down.” He turned. “Dmitry, unhook us.”

“Yes, Captain.” Dmitry swung in his seat, and headed to the laddered hatch, spinning the airtight seal, and climbing to then open the next.

Cate leant back as a draft of warm, wet air billowed into the cabin.

Jack spun in his seat. “We need to run a final check on the equipment, so we all get a few minutes to say farewell to the surface, and say hello to our new home for the next twenty-four hours. Then it’s bon voyage.” He looked to Cate. “So who’s first?”

Cate unbuckled her belt. “That’d be me.” She crossed to the ladder and waited at its base. The conning tower was small, little more than the width of the hatch. It was designed to facilitate entry and exit of personnel, and if need be, to allow docking of another submersible in the event of underwater transfers.

Dmitry slid down and nodded to her, and turned to Jack. “Tether uncoupled, Captain.”

“Good work.” Jack turned to Cate, and motioned to the ladder. “Enjoy. You’ve got three minutes.”

Cate went straight up the rungs and as soon as her head lifted above the rim of the tower she inhaled deeply and was assailed by the humidity and amazing smells of the monstrous cavern.

She shut her eyes, just using her other senses to take in the ambiance. She felt a giddy excitement as her mind created mental images of mossy rocks, beaches, drying kelp, sponges and sea grasses. She tried to blank out the small sounds coming from below and concentrate on the dark. Slowly it came – first there was the plink of dripping water, followed by its corresponding tiny echoes. Minute scratching came from some rock surface hidden away in the darkness that may have been some sort of crustacean feeding on lichen. The humidity against her skin was salty, pleasant, and like a balmy tropical evening.