“And last night . . . I think that second eruption from Tambora was even fiercer than the first. Or maybe it only seemed that way because we were much closer.”

  “No, it had to be worse,” Macklin countered. “The thunderous blast it gave off sounded like the very Earth had cracked in half.”

  “True. And the huge swell of the seas afterward did indeed feel monstrous. No doubt there’ll be even more coastal flooding throughout these islands.”

  Macklin pictured the wave that had struck Java following the first eruption. The Tenebrae had been anchored in deep water and spared any damage. Along the shore, docks had been crushed by that surge, tossing ships and debris far inland.

  “Let’s just pray we have a port to return to,” Macklin grumbled.

  By now, Lieutenant Hemple had returned to the forecastle. He moved swiftly toward the deck, his legs stiffened by urgency. “Commander, the crow’s nest reports fresh fires ahead of us.”

  “From one of the outlying islands?”

  “No, sir. At sea. Starboard side. Half-mile out.” Hemple lifted a brass spyglass. “I confirmed the same.”

  Macklin waved for the scope. “Let me see.”

  Hemple passed him the spyglass. Macklin carried it to the starboard side of the bow. As he crossed, he noted the faintest glow through the pall. He fixed the scope to his eye and took a few breaths to center and focus down upon it. He studied it for a full minute. As the Tenebrae swept toward the location, the sight grew clearer.

  “It appears to be a ship,” Macklin reported. “Aflame and listing badly.”

  “One of His Majesty’s, sir?” Hemple asked. “Or an Indiaman?”

  Macklin lowered the glass and shook his head. “Still too far off to make out any colors or flags. But we’ll strike for it, nonetheless.”

  Hemple nodded crisply and left to alert the quartermaster at the helm.

  “These seas remain hot,” Stoepker warned. “It would not be hard to imagine an errant flake of flaming ash setting torch to a wooden ship.”

  “Not on the Tenebrae. My men know what to watch for. We’ll not be caught unawares.”

  “Perhaps the other ship did not have as diligent a crew.”

  “We shall see.”

  Even at half sail, it did not take long to reach the foundering ship. By then, Macklin and Stoepker had joined Lieutenant Hemple on the quarterdeck. Master Welch manned the ship’s wheel. No one was taking any chances. Especially as it had become clear that the vessel in distress was that of a Bugi pirate, the scourge of the Dutch in this region. The ship’s masts had become torches, tilting crookedly out of the water. The hull smoked so thickly it nearly obscured the flames from view.

  Several smaller boats rowed away from the wreckage through the heavy ash. Most were also burning, smoldering, or dancing with flames. Two boats turned and headed for the Tenebrae, with oars desperately chopping the waters.

  Macklin found it strange that such pirates would seek succor aboard a ship waving His Majesty’s flag. They must know that they would only find the end of a noose if they made it here. Still, both fought hard for the Tenebrae.

  One of them caught fire. The suddenness of it drew a gasp from Stoepker. Pirates crowded into the center of the boat, as if fearing the water more than the fire. But there would be no escape from either. Clothes quickly caught the flames and the boat broke out from under them. Men tumbled into the sea, vanishing below the layer of ash. One arm burst high, still burning, then drowned away.

  “What’s happening?” Hemple asked, his eyes huge.

  Stoepker backed away from the rail. “We must leave these waters. Something is infernally wrong here.”

  As if punctuating the naturalist’s warning, a thunderous boom erupted, shaking the waters. The gloom behind them brightened with fire. It marked yet another eruption of Tambora.

  Macklin grimaced, realizing the ship’s name was proving all too apt this day. Her first owner had run her as a convict ship and fittingly named the vessel after a Catholic ceremony of punishment. The celebration of Tenebrae marked the last three days of Holy Week, when a hearse of fifteen candles, representing Christ’s travails on the way to the cross, were extinguished one after the other—until there was only darkness. The ceremony ended with a loud bang in the dark, representing the closing of Jesus’s tomb.

  Macklin stared at the sunless skies as the blast echoed away.

  Are we about to be similarly entombed?

  Moments later, the waters behind the ship swelled up, as if a great sea beast were surfacing and closing upon them.

  “Hold tight!” Hemple bellowed to the crew.

  The surge lifted the stern high, before rocking it down again, teetering the ship over the swell until she fell heavily back into the sea behind it. Afterward, the Tenebrae continued to jostle hard, waving masts and whipping sails.

  Macklin returned his attention to the last of the fleeing rowboats. Only now it had swung away and had begun striking off, as if the pirates had finally noted the flag waving high as the masts flailed in the air.

  But that was not the reason.

  Hemple rushed to his side. “Smoke, sir. Rising all around us.”

  Macklin had noted the thickening pall, but he had attributed it to the burning pirate ship.

  A boatswain and his mate burst out of the quarterdeck and hollered to all. “Fire in the bilge!”

  Hemple directed several of the crew. “Sand buckets and water! Go!”

  Macklin frowned at the sea, at the burning pirate ship.

  Stoepker leaned over the rail and looked down. “What are those?”

  Macklin followed his gaze. A tide of black stony branches clung to the lower hull. With each rock of the boat, more appeared. Smoke billowed around them, as if the branches were red-hot irons branding into the ship’s planks.

  Farther below, seen through breaks in the ash, something flashed and flickered down in the dark depths, like streams of glowing lights passing beneath and around the Tenebrae.

  Macklin shuddered at the ungodly sight.

  “Full sails now!” he ordered. “Get us out of these waters!”

  As he shouted, he never took his eyes from the sight below. Those burning branches continued to spread, climbing higher, as if the fiery claws of some briny monster had nabbed the Tenebrae.

  He now understood what had panicked the pirates.

  Before the Tenebrae could truly gain speed, flames burst along the hull and swept along those branches, encircling the ship. Even a roll into the ashy water failed to douse the fire.

  Behind him, Hemple bellowed and spread the commander’s orders. Shouts and curses rang out everywhere as desperation and terror gripped the Tenebrae.

  Macklin searched across the thickening pall toward the Bugi ship. The pirate vessel slowly sank into the ash-covered sea. He knew the same fate likely awaited the Tenebrae. It was only then that he noted Mister Stoepker and the ship’s cabin boy had vanished from his side, but he had no time to ponder their disappearance.

  As smoke shrouded his ship and flames rose to the rails, his heart pounded in his throat. He remembered the last time he had attended a Holy Week mass at the church in Batavia. A song had been sung, composed by Gregorio Allegri centuries before, marking the Tenebrae service, those last three days of Christ’s torture.

  He recited the title now, “Miserere mei, Deus.”

  It was as apt as the ship’s name.

  Have mercy on me, God.

  April 23, 1815

  Batavia, on the island of Java

  Stamford Raffles, the lieutenant-governor of the Dutch East Indies, followed the captain of the Indiaman cruiser, the Apollon, through the recovering ruins of the town’s port. Captain Haas was accompanied by his ship’s surgeon, Swann.

  The two had appeared at the governor’s palace with some urgency, carrying a letter from a man whom Stamford trusted. So, despite the late hour, with the sun sitting low on the horizon, he had set off with the men in a carriage to the docks. The group now crossed briskly down a long stone pier, one of the few still intact following the damage over the past weeks.

  Hammering and sawing and shouting echoed all around the port. But, at least, the skies had mostly cleared of ash, though a thick haze persisted that turned the sun into an angry red orb and created a perpetual twilight. The early evening’s breezes still sweltered and carried the reek of sulfur.

  Stamford held a perfumed cloth to his nose against the stench. The heat further soured his mood. He had left the palace fully attired in a black jacket and stiff waistcoat as he was due to attend a dinner later with dignitaries from British Malaya, who had come to survey the damage from Tambora’s eruption.

  Captain Haas drew alongside Stamford. The sandy-haired Dutchman was less formally dressed in gray jacket and trousers, but he kept himself neat and carried himself with a measure of practical gravitas.

  Haas waved to his ship anchored in the bay. “The Apollon was sailing from New Guinea, passing through the Java Sea, when we came upon a small boat, foundering and lost. We thought she might’ve broken free and been left adrift.”

  Swann nodded. He was a small, older man with a stern demeanor and dark eyes. “Then we spotted what the boat held. I recommended to Captain Haas that we haul it all here.”

  “We’ve not touched any of it,” Haas added, raising a silver cross to his lips, then lowering it. “Not that any of us dared to.”

  The two men drew Stamford to the end of the pier, where a small tender had been tied up. It was covered by a tarp of sailcloth. Before it stood the man who had sent the letter with the captain. It was Stamford’s aide-de-camp and trusted friend, Thomas Otho Travers. The dark-haired Irishman and former soldier kept a fit build, accented by a snug jacket and crisp trousers. He stood with a Scotsman of the same age, whom Raffles also knew, a physician of distinction, one associated with the Batavian Society, Dr. John Crawfurd.

  Both men looked equally grim.

  Stamford crossed past Haas to reach the pair. “What is it? What required such urgency?”

  Travers turned to the iron-hulled boat, which looked weathered and dented. “This tender is from the Tenebrae.”

  “What? How can you be so sure?”

  Stamford had dispatched the cargo ship, the Tenebrae, sixteen days before, but nothing had been heard from her since. All imagined the vessel had been beset by pirates, as the Bugi fleet were prowling the waters in greater numbers following the eruptions, like vultures picking at a carcass.

  “We’re certain, sir,” Travers said and turned to the physician. “Perhaps it’s best you show him, Doctor Crawfurd. I’ll help you.”

  The young physician was dressed in black with a white collar, making him look priestly. He crossed with Travers to the tender and together they drew back the drape of sailcloth to reveal a ghastly sight.

  Stamford wanted to step away, to refuse what was revealed, but Haas and his surgeon crowded behind him.

  Two bodies lay across the bottom of the tender, one twice the height of the other. Both were blackened and featureless. Still, there remained an eerie polish to their surfaces, as if both had been carved of dark marble, with a slight prickling over their skin. The smaller of the two, clearly no more than a boy, lay curled under the arm of the other. Even still, the agonized contortion of neck and spine spoke to the pain of the boy’s death. The lad had found no comfort under that arm. Still, the man had tried, even as the same torturous death afflicted him.

  Even stranger, the larger of the two had not fully succumbed to the affliction. The quarter of his body farthest from the boy remained blistered and burned at the edges, but mostly untouched past that point. An ear and cheek still shone pale and blue in death. Part of a burned white shirt hid the upper torso, and one whole leg looked untouched, still clothed in a dark pantleg and a calf-high boot.

  None of it made any sense.

  Raffles raised a foremost question. “Who are they?”

  Doctor Crawfurd stepped gingerly into the tender and over to the larger body. He pointed to the arm wrapped around the boy, then down to a blackened hand, which still bore a ring on a finger. “The stone bears the initials BG.”

  Stamford clutched his perfumed cloth tighter, knowing who had been aboard the Tenebrae. “Johannes Stoepker. The naturalist.”

  “We believe so,” Travers acknowledged. “We suspect the lad must be a cabin boy from the ship.”

  “What happened to them? No fire does this to a body. It looks like they’ve been turned to stone.”

  Crawfurd stood again, rocking the tender enough that Travers had to reach over and steady him. “We don’t know, sir,” the physician admitted. “But I did a brief examination. Whatever afflicted them has indeed petrified their flesh. Turning it hard as a rock. But I cannot fathom how or why. I’ll need the corpses carried to my rooms behind the town’s apothecary, where I can better examine the bodies.”

  “But there’s something else you should see first,” Travers warned.

  The aide-de-camp joined the physician aboard the tender and knelt next to Stoepker’s other arm, which was held tight to his chest. His stony fingers clutched a small steel box.

  “He clearly was protecting more than just the boy,” Travers said. “We didn’t want to disturb anything more until you arrived.”

  “Can you free the box?” Stamford asked. “And whatever it holds?”

  “I can try.”

  Travers wrapped his hand in a handkerchief and grabbed hold of the steel, clearly trying to avoid touching the petrified skin. He attempted to slip the box free, but to no avail. Even in death, Stoepker refused to release the secret he held.

  “With more force, Mister Travers,” Stamford demanded.

  “Yes, sir.”

  Travers planted his feet wider, then set about rocking the box and tugging hard at it. Finally, a loud snap cracked sharply, and Travers fell back to the gunwale. The tender nearly capsized under his weight, but Crawfurd balanced the other side to keep the boat from tipping over.

  A splash near the stern drew Stamford’s eye.

  He flinched. “Did you lose the box?”

  “No, sir.” Travers lifted the steel container. “I still have hold of it.”

  Stamford’s gaze remained on the water. He watched the remains of a blackened hand float to the surface, missing a couple of fingers. Despite its stony appearance, the hand clearly remained buoyant.

  What devilishness is this?

  Travers climbed out of the tender and carried the box to him.

  Stamford crossed his arms, having no desire to touch the accursed object. “Open it,” he ordered.

  Travers popped the latch and creaked the lid open. A fold of paper fell out, fluttering to the pier. Likely a last message from Johannes Stoepker.

  Stamford ignored it and leaned closer to the box. It held only one other object: a branched stalk of rock that looked like a piece of black coral.

  “What do you make of it?” Travers whispered.

  Stamford shook his head, unable to fathom any meaning to it.

  Why would Stoepker go to such lengths to preserve such a thing?

  Still, Stamford noted that the color and sheen of the fractured piece matched the blackened corpses in the tender. He also remembered a unique feature of coral: when broken and dried, their pieces often floated.

  As he stared at the ruins of Stoepker’s hand bobbing in the water, a cold certainty chilled through him.

  These bodies hadn’t been petrified into rock.

  They’d been turned into coral.

  First

  1

  January 18, 10:04 A.M. NCT

  Three hundred miles off Norfolk Island (Australia)

  Phoebe Reed stared out in awe at the sunken Garden of Eden.

  Beyond the nine inches of acrylic glass, the station’s lamps lit the perpetual darkness. They cast out a unique band of red light that caused little disturbance to the surrounding marine life. Standing at the window, she wore image-enhancing goggles tuned to the light’s wavelength to expand the view.

  Even here, two miles down, life teemed in a kaleidoscope of riches. Giant crimson-legged crabs climbed over shoals of reefs, picking delicately into crevices. Ghostly white snailfish glided over open sands. A cookie-cutter shark—once called a cigar shark due to its cylindrical shape—glowed past the window, dark on the topside, bioluminescent below. A larger shark, a bluntnose sixgill, patrolled at the edge of the light.

  Next to her, a hand pointed, noting the same. “Sixgills have never been recorded at these depths.”

  “Is that true, Jazz?” Phoebe asked, glancing over to her post-grad assistant.

  Jasleen Patel gave her a scowl for doubting her expertise. Jazz had completed her master’s degree in marine biology two years before and was finalizing her doctoral dissertation under Phoebe’s mentorship. Jazz had been one of Phoebe’s undergrad students and eventually her teaching assistant at Caltech’s marine lab. Since then, they had been working collaboratively for more than five years. So much so that Phoebe and Jazz became known as PB&J by most of their colleagues.

  Most believed the two had bonded because they were both women of color. Phoebe had been born in Barbados but raised by her mother in South Central after they immigrated to the States when she was eight. Jasleen, eight years younger than her, was a native-born Californian, but her heritage was East Indian. Her family, originally from Mumbai, ran a chain of dry cleaners across the Bay Area.

  But it wasn’t the women’s skin color or gender that drew them together. At least, not entirely. It was much more about their mutual interests in the mysteries of the deep. That, and their respect for each other.

  “It’s hard to believe anything could survive in this sunless bathypelagic zone,” Jazz said, placing a palm against the glass. “The pressure out there is more than two tons per square inch.”

  “It’s exciting, isn’t it. Life not only took a foothold out there, but it’s thriving in great abundance.”

  They both gazed at the wonderland beyond the glass.

  A couple of anglerfish dangled their long rods, waving their luminescent lures. Clutches of squidworms squirmed through the light, feeding on marine snow that fell from the sunlit levels, bringing energy down to these midnight seas. Every glance around her revealed more: schools of viperfish, a pair of vampire squids, a single dumbo octopus. Farther out, albino lobsters crawled amidst waves of crimson anemone.