“I sympathize with your problem, sir, but I can’t give you permission to use the Hardsuit. That would have to come from higher up. I’ll connect you.”

“I’ll deal with the Navy brass,” Austin said with thinly veiled annoyance. “I just want to know if the new Hardsuit can dive a half mile.”

“That’s what the tests were supposed to determine,” the officer said. “The weak spots in an ADS have always been the joints. With the new joint design, theoretically it’s possible to go deeper, maybe to five thousand feet. But if there is one tiny flaw, you could have a massive failure.”

Austin thanked the officer and said he would clear the dive with the officer’s superiors, although he didn’t say when. He hoped to be unavailable by the time the Navy bureaucracy reacted.

While Austin had been discussing the Hardsuit with the officer, a nagging thought had been buzzing around in his head like a hungry mosquito. Heading back down to the ROV control center, he found the young woman who had tracked the ROV still sitting at her station. He asked her to rerun the last sixty seconds of its video. She clicked her mouse and the sea bottom a half mile down appeared on the screen. Once again, Austin watched the ROV soar like a bird over the undulating vegetation covering the seafloor. Its camera soon picked up the splatter from the B3’s impact, then the bathysphere’s dome protruding from the crater.

“Freeze the image right there,” Austin said. He pointed to a dark area in the upper-left-hand corner of the screen. “Now, run it in slow motion.”

The shadow moved off the screen.

The ROV operator stared at the screen, jutting out her lower lip. “I don’t remember seeing that.”

“It was easy to miss,” Austin said. “We were all focused on finding the bathysphere.”

She sat back, folded her arms, and focused on the oblong shape that was barely visible at the edge of the searchlight beam.

“Might be a fish or whale,” she said, “but something about it isn’t quite right.”

Austin asked the operator to enlarge the image. It broke apart as it was blown up, but Austin nonetheless detected a vague manta-ray shape to the shadow. He asked her to print the image, and to play back the final transmission from the bathysphere.

The operator ran off a printout, then reduced the shadow image and tucked it in the upper-right-hand corner of the screen, which now displayed a picture of Kane. He was rattling off an excited description of the luminescent fish swimming around the bathysphere when suddenly he stopped short and pressed his face against the window.

“What was that?” Kane said.

The voice-activated camera switched to Zavala.

“You see a mermaid, Doc?”

Back to Kane.

“I’m not sure what I saw, but I know one thing: it was big!”