The writing app for the whole book.

At 18:10 the westerly came hard over Gannet's Wake, driving rain beneath the harbour eaves. Mara Venn had one hand on a tin of lampblack when she heard the net pull tight.

The sound was small under the gale: a wet rasp, then a thin, furious cry. A tarred net had snagged against the mooring posts. Something moved inside it.

Mara set down the tin and worked her knife beneath cords stiff with salt and pitch. A soot-dark cat forced his head through the opening. One forepaw was pale; the other claws were buried in the twine.

“Easy,” she said, though the cat had no reason to believe her.

She cut strand by strand. When the last cord released, the cat shot beneath the chandlery bench and stopped, sides heaving. Mara crouched and held out her fingers. He watched them, wary and shivering.

Northlight could not wait, said the part of her trained to count every minute. The part that had seen the net tightening knew what waiting meant.

She wrapped the cat in her scarf. He weighed almost nothing. Under the chandlery awning she rubbed him with a dry sack until his pale paw showed again, then tucked him inside her coat.

“Beacon,” she told him, looking towards the storm-blurred tower. “That is what you are.”

Then she took up the lampblack and ran uphill, already late.

By 18:25 Mara had reached Northlight with the cat inside her coat. Rain ticked against the lantern-room glass. Keeper Doss stood beneath the dead-grey lens.

“Lampblack first,” he said. “Then the cat. Not the other way round.”

Mara put the tin on the bench. “The net was tightening.”

“Everything tightens in a gale.” Doss's gaze moved to the soot on her sleeves. “You have been eighteen months in this apprenticeship, Mara. Eighteen months is long enough to know an errand is an errand.”

Jonas Pell, the twenty-eight-year-old senior lamplighter, was sparing with words. He closed the wick drawer and looked at the cat emerging from Mara's coat.

“The net would have killed him,” Jonas said.

Doss's mouth hardened. “And if the lampblack is late, the lens may sulk all night.”

Jonas picked up the tin and carried it to the service shelf. “Then we will clean twice. Keeping a light is noticing what can fail, Keeper. That includes what rank overlooks.”

Mara knew the lens-cleaning sequence, the count of the weights, the knots that held a storm line. She still waited for Doss to tell her when knowledge became authority.

The cat pressed against her ankle. Jonas set a folded rag beside the stove without comment. Doss turned to the logbook, and the wind worried the tower walls.

At 18:40 Neri Quill came up from the quay with the signal slate under their jacket. Fourteen and unsponsored, they were ignored by visiting captains. Mara had read their timings. They were exact.

“Five vessels from the Ash Isles,” Neri said. “Lead ship at Needle Shoals by midnight if the wind holds. It will not hold.”

Mara entered the figures. Below, Hask Fen's chandlery cart rolled through the lower supply door. Its paraffin tins were tied with red sail-twine, each lid marked blue. Hask smiled when Doss waved him through.

Jonas watched the delivery, then checked the stores. His brass service key hung from his belt. Later, while Mara counted the clockwork weights, he used it on the governor housing. The rotation stuttered for one breath.

“There,” Mara said.

Doss listened to the mechanism. “Old teeth. They complain before they break.”

“The timing is losing half a beat every turn.”

“Then record half a beat.”

She did. On the next page she noted the blue paraffin, red twine, and reserve-inventory mismatch. In the store cupboard, Jonas's shorthand beside the wick height and oil line showed a four-wick lamp had been tested recently.

At 19:35 Jonas fed Beacon from a chipped blue dish behind the stove. The cat crept close only after Jonas stepped back. Mara saw him pretend not to watch.

Beacon ate until the blue pottery showed clean.

“The reserve lamp is sound?” she asked.

“Sound enough,” Jonas said. “If we need it, we will know.”

Doss shut the log. “Hask's papers are in order. Jonas has the key because he is senior. You have a list of worries because you are an apprentice.”

Mara looked at the blue tins, the governor, and the marks for the last lantern. The separate facts made one shape in her mind. Doss had already turned away.

At 20:00 Northlight went dark.

The lens stopped turning first. Its beam slid across the wet harbour wall and vanished. Then the mantle gave a soft cough, and the lantern room filled with the smell of hot paraffin and rain.

Mara reached the governor housing before Doss. The cut was clean. Not a worn tooth, not a broken spring: a deliberate slice through the governor's retaining cord. Below it, the main feed hose had been severed and its valve pinched shut.

“No one touches anything,” Doss said.

But Jonas was not there.

Neri appeared at the stair, breathless. “I saw Hask leave by the lower door. Before the dark.”

Doss crossed to the service bench. Jonas's brass key lay on the boards beside the cut cord, wet with rain. Its ring had left a clean circle in the dust. Mara stared at it. Jonas never set it down except to work.

“He opened the housing,” Doss said. “He cut the governor. Then he ran.”

The words fitted too neatly. Outside, the five Ash Isles ships were somewhere beyond the cloud, sailing towards the shoals with no light to find.

Mara picked up the key only when Doss told her to. Its teeth were cold in her palm. The tower's clockwork stood still, and Jonas remained absent.

At 20:10 Doss barred the lantern-room stair with his arm.

“Harbour authority is being sent for,” he said. “Until then, nobody repairs, searches, or leaves.”

“The fleet reaches Needle Shoals at midnight.”

“Which is why we do not make a second mistake.” He took the brass key from Mara's hand. “Jonas knew the governor. Jonas knew the reserve. We wait for the harbour master to decide what his absence means.”

Mara went back to the stove because there was nowhere else she was permitted to go. Beacon slipped from beneath the bench and crossed the floor. He paused at a smear of soot by the skirting board, sniffed, and followed the wall towards the stores.

The chipped blue dish stood behind the stove. It held fresh fish although Beacon had licked it clean less than an hour ago. Someone had filled it again. A narrow soot trace ran from the dish to the cupboard's low edge, where it vanished beneath a warped board.

Mara knelt. The trace was too broken to be a message. It could have been a boot, a sack, a cat. It could have meant Jonas had fed Beacon and gone by the ordinary door. It did not prove innocence.

Doss's voice came from the stair. “Mara.”

She looked at the dark glass above him. Waiting was an order, but it was also an action. Every quarter hour spent defending the order carried the ships nearer the shoals. Her training said permission came before authority. The dead lamp offered no permission at all.

Beacon rubbed against her knee, safe and warm, then turned towards the lower passage. Mara took her coat from its peg.

“Where are you going?” Doss asked.

“To listen for the first signal.”

It was not a repair. It was not yet disobedience. But at 20:30, with Northlight dark and the wind rising, Mara chose not to wait.

The first horn note came through the stone as a dull knock. Neri saw three pale flashes beyond the rain and called their timing from the landing.

“They have the shoals under them,” they said.

Doss answered from the stair. “We wait for harbour authority.”

Mara looked at the dark lantern room, then lifted the repair log from Doss's desk. Waiting had become a decision made for the people on those ships. “Neri, take the signal slate to the east window. Mark every flash and call the intervals. If the pattern changes, shout down.”

“You are giving orders,” Doss said.

“I am recording the fleet and repairing what we can.” Her voice shook once, then steadied. “Those are not the same as taking your post.”

Neri had already taken the slate. Mara lifted the bar from the lower works door. Beacon slipped past her boots, following warmth and the fish smell in her pocket, and vanished down the stair.

The lower works smelled of damp stone and paraffin. The dead feed hung above them, its severed end black with oil. Mara set down her lamp and read Jonas's marks: governor first, feed second, shutters before the lens.

She touched the empty space where he had drawn the service lock. His key lay beside the damage, but his method still held. From above, Neri called another interval. Mara tightened her sleeve knot and took the wrench. The route below was no longer an inspection. It was the work.

At twenty forty-five Neri came down between signals while Mara worked the seized governor free. Their slate held a cleaner record than the tower's official log.

“How long have you kept those?” Mara asked.

“Since the Ash Isles notice. Doss says signals are harbour work.”

“Then he has mistaken the harbour for separate pieces.”

Neri handed her the spanner. “Jonas did not. I saw him after the last watch change with an oil tin without the blue mark. He carried it towards the abandoned fog-bell gallery.”

“Did he look frightened?”

“He looked back twice. As if checking whether someone followed.”

The sighting could make Jonas worse, not better. Unmarked oil on the hidden route was still oil on an unauthorised route.

Beacon went to the chipped blue dish and sniffed its rim before facing the gallery. “He trusted Jonas,” Neri said.

“He trusted food.”

“He knows the difference between a boot and a hand.”

Mara watched the runner's pencil move. Accurate, patient, overlooked. “You are my second set of eyes now. Watch the fog-bell door and keep the timings.”

Neri nodded. “And if Jonas is there?”

“We record what we find before deciding what it means.”

The governor clicked once beneath Mara's hand. Neri returned to the east window by way of the fog-bell passage, slate ready, while Beacon followed Jonas's familiar fish scent towards the gallery. Shared attention, Mara thought, was how they kept from mistaking one piece of evidence for the whole machine.

The lower works yielded by inches. Mara freed the lens gear one tooth at a time while Neri tested the shutters against Jonas's sequence. A bent pin became a straightened nail; a chain lifted without grinding. Small answers made the tower feel briefly repairable.

Beacon followed warmth and paraffin into a gap behind the stores. Mara did not send a hand after him. The crawlspace was too tight, and he had gone in by choice.

He returned dusty and annoyed. Blue oil shone on his pale paw. A strand of red sail-twine clung to his coat.

Neri touched the torn cord. “Hask's delivery twine.”

The oil smear ran from the gap towards the lower door. It located the gang's bypass. But Jonas had carried unmarked oil towards the same gallery. Two trails could cross without belonging to the same person.

Mara marked the path on the repair log. Neri tested the lower latch and found its inner face rubbed bright, as though repeated boots had passed through it. The blue oil was fresh enough to shine, but neither of them could say whose hand had spilled it.

“We keep the cord,” Mara said. “And a record of the stain.”

Neri sketched the small blue smear before rain from the wall blurred its edge. “Evidence before meaning.” Mara folded the twine into a clean corner of her wiping cloth and put both in her pocket.

Beacon shook himself clear. Mara dampened a corner of her cloth and wiped the blue from his pale paw before he could lick it, then set him on clean stone. Mara and Neri returned to the shutters. The smaller mechanisms were ready; the main feed remained cut. Somewhere beyond the stone, the false route and the honest one shared a door.