Wagner didn’t respond. Eunice focused on the ghostly picture that the sonar provided. They were within a few meters of a whale fall, and according to her velocity sensors, it was especially active.
Eunice cast a cautious ray of light across the scene. This fall was in its second stage, which implied that it was less than two years old. Most of the whale’s soft parts had been devoured, with fleshy clusters of worms and curtains of bacteria hanging from the bones like cobwebs, and hagfish were everywhere. They were up to half a meter in length, with loose gray skin and flat tails, and they tied themselves in knots in their struggle to burrow deeper into the carcass.
She passed the light from one end of the seafloor to the other. The bacteria here were already at work, and the sediment would be full of sulfides, but she disliked it. When you had company, it only meant that more could go wrong, but she didn’t have much of a choice. “I’m going closer.”
As she circled the scene, the hagfish became more active when they were hit by the light. She knew that they wouldn’t bother her if she kept her distance, but the tricky part would be finding a spot that was out of the way—
A shadow entered her line of vision. It had been hanging motionless at the edge of the fall, and she had just a fraction of a second to take in its blank white eye and huge mouth before it attacked.
Eunice cut the light, but it was too late. A sleeper shark could drift like a dead thing in the water for hours, but when it detected prey, it could move with shocking suddenness, like a trap poised to spring shut at the smallest disturbance. It came at her, jaws wide, and before she could defend herself, it was sucking her in. She fought back frantically, but the shark had already seized her hemisphere and one of her arms. Eunice felt its sharp upper teeth seeking for purchase in the smooth surface of her dome, pressing down savagely as it swung its huge head in a circle.
Around her midsection, Wagner lit up at once with full awareness. “What is it?”
Eunice couldn’t speak. One of her limbs was caught, but the others were free, and as the shark strained to swallow her, she flung her two nearest arms upward, pressing down hard against the sides of its skull. She dug into something soft. Eunice wasn’t sure what it was—it might have been its left eye—but she pinched her fingers down into a point and pushed into the opening that she had found.
A spasm ran through the shark’s body. Groping with her other limb on the right side of its head, she found a second tender spot and drove into it. The shark bit down convulsively. Eunice plunged her arms in further, trying not to think about what was giving way beneath, and did the same with the limb in the shark’s mouth, pushing down its throat and bending up through its palate.
Oil and blood filled the water. The shark kept fighting, its brain sending out frenzied signals until the very end, but at last, it relaxed. Eunice extracted her arms one at a time and managed to free herself. As the shark’s body drifted to the seabed, the water came alive with movement. She braced for another assault, but it was only the hagfish, drawn to the new bounty that had unexpectedly appeared.
Eunice made it to the edge of the fall and buried herself in the sand, trying to become as small as possible. Her sensors indicated that there was nothing else nearby, but she still waited, motionless, until she was certain that she was alone. Finally, she found her voice. “Get to work.”
Wagner detached with what felt like uncharacteristic reluctance. He did not ask what had happened. As he crawled away, Eunice remained on full power. She was shaken by the close call, and as she monitored the area with everything but her eyes, she became aware of another emotion.
It was grief. The shark had been a living being that had only sought its own survival. If she had been more careful, she would have detected it before it had a chance to attack, and they might have left each other in peace. Instead, she had killed it with her own carelessness, and as she mourned it, she felt overwhelmed by the sudden knowledge that she would never make it home.
III.
In the months that followed, Eunice found herself thinking more intensely about time. As she traced her wandering path from one whale fall to another, the shark faded to a distant memory, floating at the edges of her consciousness. Yet it was always there, lurking silently, and it came to stand for all the unknowns that she had yet to confront, like the prospect of death in the mind of someone living.
After the attack, Eunice had spent the next few days checking all of her systems. She found no evidence of serious damage, and as soon as Wagner had recharged, she set off again, leaving her lights extinguished. Whenever she returned to the fall where she had encountered the shark, her fears rose again, and although she met no other predators, she was still relieved when she finally discovered another fall that would allow her to move on.
But something had changed. In the past, she had allowed herself to fantasize about what she might find at her destination—James, the charging station, the seven sisters she had left at home. Sometimes she had even imagined seeing Galatea and the others from the vent system, as if they had miraculously made it back on their own. It had been a kind of dreaming in advance, but now she pushed such thoughts away, until only the image of the tether remained.
Occasionally, there would be a break in her routine. One came whenever she arrived at a new hydrothermal vent. The first one after the shark attack had been relatively fresh, with lava flows shining with glass, bundles of tube worms two meters high, and sessile jellyfish clinging to the rocks. Eunice tried to draw comfort from the sight, and she was tempted to stay, but she finally moved on. Even a vent would not last forever, and sooner or later, she would break down herself.
A few days afterward, she finished recharging at a new whale fall and went to the surface to check for signals. She was rising into the photic zone, the water around her gradually brightening, when her velocity sensors picked up a change. Something large was directly overhead.
It was a whale. Eunice slowed her ascent, gazing up in wonder as it passed across her field of vision, outlined by the faint glow of the sun. It was fifteen meters long and dark gray, its skin covered with the pale patches left by parasites. She could make out the parallel furrows that ran along the underside of its throat. Looking to one side, she saw another whale, and then another. She hung there until the tenth and final whale had passed, accompanied by a smaller shape, nearly black, that was swimming at its flank. It was a mother and her calf.
As she watched the pod pass by, transfixed, Eunice was filled with longing for Thetis, Galatea, Dione, Clio, and the seven sisters who had remained in Seattle. She wondered bleakly if Galatea was still at the vent, or if she had been swept away when the mining began—
A second later, her spell was shattered by a shock of realization, and before she knew what she was doing, she was swimming as fast as she could after the whales. By now, the pod was hundreds of meters away, but she was unable to abandon the possibility that had suddenly occurred to her.
She dumped her lower tanks, allowing her to rise more rapidly, and propelled herself madly onward. Noticing the change, Wagner stirred underneath her dome. “What’s going on?”
Eunice said nothing. The whales were heading north, on their usual migration route, along a path that coincided with the coastline. If she could latch on to one of them, finding a place where she could ride unnoticed, she could cling there for as long as possible, traveling hundreds of kilometers without expending any additional energy. All she had to do was get to them now.