"All OK?" the rowboat-him asked the meat-him.
"I’m in," he replied. He looked at the air-gauge on his BCD. 700 millibars—less than half a tank of nitrox. He spat in his mask and rubbed it in, then rinsed it over the side, slipped it over his face and kept one hand on it while the other held in his regulator. Before he inserted it, he said, "Back soon with Kate," and patted the row-boat again.
Robbie the Row-Boat hardly paid attention. It was emailing another copy of itself to the Asimovist archive. It had a five-minute-old backup, but that wasn’t the same Robbie that was willing to enter a human body. In those five minutes, he’d become a new person.
Robbie piloted the human-shell down and down. It could take care of the SCUBA niceties if he let it, and he did, so he watched with detachment as the idea of pinching his nose and blowing to equalize his eardrums spontaneously occurred to him at regular intervals as he descended the reef wall.
The confines of the human-shell were claustrophobic. He especially missed his wireless link. The dive-suit had one, lowband for underwater use, broadband for surface use. The human-shell had one, too, for transferring into and out of, but it wasn’t under direct volitional control of the rider.
Down he sank, confused by the feeling of the water all around him, by the narrow visual light spectrum he could see. Cut off from the network and his telemetry, he felt like he was trapped. The reef shuddered and groaned, and made angry moans like whale-song.
He hadn’t thought about how hard it would be to find Kate once he was in the water. With his surface telemetry, it had been easy to pinpoint her, a perfect outline of human tissue in the middle of the calcified branches of coral. Down here on the reef-wall, every chunk looked pretty much like the last.
The reef boomed more at him. He realized that it likely believed that the shell was still loaded with its avatar.
Robbie had seen endless hours of footage of the reef, studied it in telemetry and online, but he’d never had this kind of atavistic experience of it. It stretched away to infinity below him, far below the 100-meter visibility limit in the clear open sea. Its walls were wormed with gaps and caves, lined with big hard shamrocks and satellite-dish-shaped blooms, brains and cauliflowers. He knew the scientific names and had seen innumerable high-resolution photos of them, but seeing them with wet, imperfect eyes was moving in a way he hadn’t anticipated.
The schools of fish that trembled on its edge could be modeled with simple flocking rules, but here in person, their precision maneuvers were shockingly crisp. Robbie waved his hands at them and watched them scatter and reform. A huge, dog-faced cod swam past him, so close it brushed the underside of his wetsuit.
The coral boomed again. It was talking in some kind of code, he guessed, though not one he could solve. Up on the surface, rowboat-him was certainly listening in and had probably cracked it all. It was probably wondering why he was floating spacily along the wall instead of doing something like he was supposed to. He wondered if he’d deleted too much of himself when he downloaded into the shell.
He decided to do something. There was a cave-opening before him. He reached out and grabbed hold of the coral around the mouth and pulled himself into it. His body tried to stop him from doing this—it didn’t like the lack of room in the cave, didn’t like him touching the reef. It increased his discomfort as he went deeper and deeper, startling an old turtle that fought with him for room to get out, mashing him against the floor of the cave, his mask clanging on the hard spines. When he looked up, he could see scratches on its surface.
His air gauge was in the red now. He could still technically surface without a decompression stop, though procedure was to stop for three minutes at three meters, just to be on the safe side.
Technically, he could just go up like a cork and email himself to the row-boat while the bends or nitrogen narcosis took the body, but that wouldn’t be Asimovist. He was surprised he could even think the thought. Must be the body. It sounded like the kind of thing a human might think. Whoops. There it was again.
The reef wasn’t muttering at him anymore. Not answering it must have tipped it off. After all, with all the raw compute-power it had marshaled it should be able to brute-force most possible outcomes of sending its envoy to the surface.
Robbie peered anxiously around himself. The light was dim in the cave and his body expertly drew the torch out of his BCD, strapped it onto his wrist and lit it up. He waved the cone of light around, a part of him distantly amazed by the low resolution and high limits on these human eyes.
Kate was down here somewhere, her air running out as fast as his. He pushed his way deeper into the reef. It was clearly trying to impede him now. Nanoassembly came naturally to clonal polyps that grew by sieving minerals out of the sea. They had built organic hinges, deep-sea muscles into their infrastructure. He was stuck in the thicket and the harder he pushed, the worse the tangle got.
He stopped pushing. He wasn’t going to get anywhere this way.
He still had his narrowband connection to the row-boat. Why hadn’t he thought of that beforehand? Stupid meat-brains—no room at all for anything like real thought. Why had he venerated them so?
"Robbie?" he transmitted up to the instance of himself on the surface.
"There you are! I was so worried about you!" He sounded prissy to himself, overcome with overbearing concern. This must be how all Asimovists seemed to humans.
"How far am I from Kate?"
"She’s right there! Can’t you see her?"
"No," he said. "Where?"
"Less than 20 centimeters above you."
Well of course he hadn’t see her. His forward-mounted eyes only looked forward. Craning his neck back, he could just get far enough back to see the tip of Kate’s fin. He gave it a hard tug and she looked down in alarm.
She was trapped in a coral cage much like his own, a thicket of calcified arms. She twisted around so that her face was alongside of his. Frantically, she made the out-of-air sign, cutting the edge of her hand across her throat. The human-shell’s instincts took over and unclipped his emergency regulator and handed it up to her. She put it in her mouth, pressed the button to blow out the water in it, and sucked greedily.
He shoved his gauge in front of her mask, showing her that he, too was in the red and she eased off.
The coral’s noises were everywhere now. They made his head hurt. Physical pain was so stupid. He needed to be less distracted now that these loud, threatening noises were everywhere. But the pain made it hard for him to think. And the coral was closing in, too, catching him on his wetsuit.
The arms were orange and red and green, and veined with fans of nanoassembled logic, spilling out into the water. They were noticeably warm to the touch, even through his diving gloves. They snagged the suit with a thousand polyps. Robbie watched the air gauge drop further into the red and cursed inside.
He examined the branches that were holding him back. The hinges that the reef had contrived for itself were ingenious, flexible arrangements of small, soft fans overlapping to make a kind of ball-and-socket.
He wrapped his gloved hand around one and tugged. It wouldn’t move. He shoved it. Still no movement. Then he twisted it, and to his surprise, it came off in his hand, came away completely with hardly any resistance. Stupid coral. It had armored its joints, but not against torque.
He showed Kate, grabbing another arm and twisting it free, letting it drop away to the ocean floor. She nodded and followed suit. They twisted and dropped, twisted and dropped, the reef bellowing at them. Somewhere in its thicket, there was a membrane or some other surface that it could vibrate, modulate into a voice. In the dense water, the sound was a physical thing, it made his mask vibrate and water seeped in under his nose. He twisted faster.