Saitō gave a small nod. “Then don’t give them the chance.”

  He pressed Confirm.

  The shipboard AI spoke at once, its voice as cold as a knife drawn through air:

  “Hull-lowering procedure initiated. Countdown: ten, nine, eight…”

  The depth field on the screen reset to zero; the next second it began to jump.

  No one spoke in the operations bay. Even breathing grew lighter, as though noise might wake something.

  When the countdown reached zero, it did not feel like a machine descending so much as a hand being placed into the sea. The sea was vast; the hand was small. The sea never hurried. It only needed to wait.

  At the first instant of descent the bay took on a light tremor, as if someone had rapped twice on the underside of the hull.

  The AI followed with the same temperatureless calm:

  “Gray Whale entering deep-submergence mode. Compartment seals confirmed. Cabin pressure regulation initiated. Ballast system engaged. Thrust vector locked. ROV secured in the vehicle bay, locked standby, descending with vessel. Internal links nominal. Awaiting release.”

  The ROV had not yet been released. It sat locked in the vehicle bay beneath Gray Whale, clamped to its release frame like a metal animal with its claws folded away. During descent it did no work; it merely went down with the boat.

  So the displays were mostly attitude, cabin pressure, ballast, thrust vector—numbers that meant survival. On the ROV page it was self-check and standby: power status, lock status, sensor warm-up. Once Gray Whale reached station and stabilised, they would let it go—send it out to become their eyes and hands.

  Then a low wash of water moved through the bulkheads—not waves, but ballast exchange: water drawn in, water expelled, a steady whoosh—whoosh— running the pipes, as though the boat were weighting herself, as though weight could be a kind of composure.

  Raphael glanced up at the overhead without meaning to, voice pressed low. “There it is again.”

  Anika didn’t look up from her page. “All seal lights are green. Don’t start inventing ghosts.”

  Saitō’s hands were already braced at the console edge, knuckles tight. “Keep the descent rate steady. Get through the shear layer first. Don’t steal speed.”

  The AI began to count:

  “Gray Whale depth: ten. Twenty. Thirty.”

  Outside, the light thinned quickly. At first the camera still caught a trace of blue—like old glass. Deeper down, the sea swallowed the blue in mouthfuls: distance first, then near. Around a hundred metres, the “world” on the feed became only the small patch the ROV lamps could carve out; everything else was black.

  The hull shivered.

  Not a violent shake—more a minute groan under pressure. A brief kree— came from inside the walls, short and light, and in that quiet it sounded painfully clear, like steel gritting its teeth.

  Raphael’s hand stopped on the chairback. He swallowed. “I still can’t get used to that noise.”

  Keiko didn’t lift her head; she only keyed in the timecode. “Log: depth one hundred. Cabin pressure regulation ongoing. Hull compression noise detected.”

  The AI added, as if spelling it out:

  “Cabin pressure maintained within operational standard. Hull stress nominal. Ballast exchange ongoing.”

  Anika watched the communications bit-error rate curve. “External radio signal’s dropping. The deeper we go, the more it feels like being stuffed into a well—and someone’s closing the mouth.”

  Saitō tapped the propulsion page. “Hold thrust vector. Don’t let attitude drift. If the boat drifts, the tether angle gets torn.”

  The AI prompted: “Current shear intensity rising. Thrust-vector micro-adjustment recommended.”

  The change was so fine they felt it rather than saw it—like someone in the water giving the boat’s tail a small, precise nudge. The thrusters didn’t shove; they corrected by degrees. The feedback strip along the console edge flickered: “Vector +1°, ?2°, +1°,” as though adjusting the balance of a tightrope walker.

  Raphael stared at the attitude plot. “We’re sliding.”

  Saitō’s voice stayed level. “I know. Micro-adjust. Don’t try to bully the current. Bully it and the tether goes straight.”

  The ballast ran another pulse—whoosh—whoosh——a kind of heartbeat. The roll amplitude eased down, becoming duller, steadier, but also heavier.

  The AI reported: “Gray Whale depth: one-fifty. Current shear strengthening. Reduced speed recommended.”

  Unlawfully taken from Royal Road, this story should be reported if seen on Amazon.

  Saitō gave the order at once. “Drop one notch.”

  “Descent rate reduced,” the AI confirmed.

  On the feed the suspended particles thickened, like snow stirred into a cloud. Here the current layer was a blade; the water wasn’t still, it cut in at a slant. The picture jolted twice. Then came a brief scatter of white—digital snow.

  Anika’s tempo sharpened. “Dropped frames. Back. Dropped again. BER rising.”

  Keiko stamped the log. “Log: depth one-eighty. Short-duration frame loss.”

  Raphael muttered a curse. “Don’t you dare give me a scrambled screen now.”

  Saitō didn’t spare him a glance. “Hold two seconds. Stabilise attitude. Let it stand.”

  The thrust-vector strip shifted. The fine vibration in the bay softened, as if someone had pressed a palm down on it. The snow broke up. The picture returned, a little clearer.

  The AI added: “Attitude stabilised. Tether angle returned to safe range. Tension within controllable interval.”

  Raphael watched the tension curve. It floated up and down inside the safe zone—small amplitude, but each upward twitch felt like fingers pinching a heart. He breathed out. “That line frightens me more efficiently than I ever could.”

  Keiko answered without emotion. “It frightens you so you stay alive.”

  Depth kept increasing.

  “Gray Whale depth: three hundred,” the AI reported. “Current shear reduced. Entering relatively stable layer.”

  Hull compression noises eased. Ballast exchange slowed, its rhythm turning from urgent to patient. The blade-layer had passed, but the pressure grew heavier—and that heaviness wasn’t on skin. It pressed on eardrums, on the inside of the chest. You found yourself swallowing just to prove your throat still belonged to you.

  Anika murmured, “External signal’s almost gone.”

  Saitō watched the thrust-vector feedback, adjusting parameters with slow fingers. “Keep this tempo. Another two hundred. Keep the ROV tucked close—don’t snap the link.”

  The AI counted:

  “Gray Whale depth: five hundred. ROV depth: five hundred. Cabin pressure stable. Hull stress nominal.”

  On the screen the seabed began to surface out of the black, like crumpled dark paper. On the sonar return, messy textures assembled in blocks—mostly natural undulations, nothing with manners.

  Then, inside that disorder, something clean appeared.

  A nearly straight edge. Then—a sharp corner.

  Anika spoke first. “That return’s wrong.”

  Keiko stamped time. “Log: anomalous return, first occurrence.”

  Raphael stared at the screen, his voice dropping of its own accord. “That isn’t natural. Nature doesn’t do squares out of kindness.”

  Saitō didn’t explain. He zoomed the return and kept the thrust-vector page open beside it. His fingertip paused on the straight line, like a hand hovering at a closed door.

  “Go closer,” he said. “See it clean. Don’t guess.”

  The shipboard AI remained calm as a verdict:

  “Target-zone return strengthening. Fine-search mode recommended.”

  Ballast ran another whoosh, as though the boat adjusted her posture in the deep. Gray Whale continued descending; the darkness pressed down like wet cloth. That right-angled echo waited in the centre of the display—waiting for them to deliver themselves to it.

  In the deep sea, what a human can do is limited. What a machine can do is also limited. Gray Whale carried three systems, each with its own trade.

  AUV (autonomous underwater vehicle: a sonar “paintbrush”): a self-navigating sonar “brush” that sweeps the target zone’s contours first, filtering out most useless ground. It isn’t delicate, but it covers area—good for deciding where is worth looking.

  Bee: a micro-scout that slips into seams and takes close-range evidence—interfaces, cracks, lift points—clean and undeniable. It doesn’t work; it exists to make sure you see clearly before you decide.

  ROV (tethered remotely operated vehicle: a “mechanical hand” in the deep): tethered, tool-headed, with manipulators for the real labour—jetting silt, rigging lift points, dragging and recovery. A person sits in the bay, but their hands reach the seabed.

  Saitō flipped between the three pages, his tone precise. “Don’t reverse the order. AUV scans first—find something worth looking at. Then Bee goes in to confirm position and condition. Only then does the ROV go out to work. Today we don’t bet on luck. We only do what we can prove.”

  Raphael nodded. “Understood. Find first, then see it properly, then move. No reaching into the dark and pretending it’s bravery.”

  Keiko added, “Write the sequence into the log. Anyone who jumps steps—when something goes wrong later, you won’t know why.”

  Anika wasn’t operating the tools, but she warned them anyway. “When you deploy the AUV and the Bee, keep the comms chain clean. Don’t let noise tilt your judgement.”

  Saitō lifted a hand—short, crisp, like calling a classroom to order. “AUV first. Grid scan the target zone. One uplink every three minutes. Start.”

  The AI answered immediately:

  “AUV deployment preparation. External hardpoint unlock. AUV entering autonomous route mode. Scan grid loaded.”

  Once the AUV was out, it felt as though the bay had gained an eye that never blinked.

  The screen stopped being “one beam of light in black” and became a sonar map assembling itself piece by piece. Cold blocks of tone laid down like pencil shading: rise here, dip there; silt thickness; return strength—everything compressed into a map with no mercy.

  The AI kept time:

  “AUV Route One: twenty per cent complete. Uplink nominal. Seafloor texture stable.”

  Raphael watched, tapping the wall of his cup. “Looks like a cemetery plan. All we’re missing is names.”

  Keiko didn’t look up. Her finger stamped another timecode. “Don’t talk. Let it finish the sweep before you decide.”

  Saitō ignored the mood. He nudged the AUV return threshold and switched on linear-feature detection. Seconds later, a hard line appeared—so straight it stung the eye. Beside it: a clean angle, too orderly to be born.

  The AI prompted: “Non-natural geometric edge detected. Marking as priority target recommended.”

  Saitō replied, clipped. “Mark it. Zoom. Switch to dense grid.”

  The AI complied. The AUV began running tight passes over that small patch; the grid thickened, the outline sharpened. Whatever it was lay buried in silt, barely exposed, but its edges were clean—like the corner of a box smeared over with mud.

  Raphael frowned. “A corner. You sure it’s not a rock face?”

  Saitō watched the echo shape. “Rock doesn’t behave this neatly. Rock doesn’t return this consistently. Looks like a casing.”

  Keiko began typing: “Log: AUV detected non-natural geometric structure; preliminary assessment: artificial container exposure; timestamp—”

  Saitō wouldn’t let preliminary settle into guess. He lifted a hand. “Bee out. Into the seam.”

  The AI announced:

  “Bee deployment preparation. Micro-thrusters warming. Lamp on. Close-range imaging mode ready.”

  The view cut—into a different world.

  The Bee’s camera was an eyeball flying inches above the seabed. Its light spot was small; only what it illuminated existed. It slid along the AUV-marked edge. Silt drifted through the beam, circling the lens like dust.

  Up close it became clear: not rock, but the corner of a metal shell—coating flaked at the edge, the surface crusted with hard deposits.

  Raphael lowered his voice. “It really is a box.”

  This wasn’t good news.

  It was trouble.