Mara put two fingers to the chalk. It came away in a white paste.
"Less than an hour," she said.
Another shot struck the lip of the opening. Stone spat into the water. Ivo fired back without aiming long enough to deserve success, then dragged the hammer down on an empty chamber.
"That was my last," he said.
"You might have mentioned it before spending it on a face."
"I disliked the face."
Teren had Sabine against the cistern wall, his knee braced behind her shoulder. What remained of the splint hung by one strip of linen. Blood ran from beneath the binding in narrow dark threads and vanished into the water.
"The hand is warm," he said. "Mara. Can you keep it so?"
She looked once. Sabine's fingers were grey at the nails, the skin swelling around two rings she had refused to remove even while crawling through a flooded conduit.
"Cut those off. Now."
Sabine lifted her head. "One is the house seal."
"Then the house may lose a finger with you."
Ivo drew his knife. It was the narrow forest blade he sharpened when conversation threatened to become honest. He wedged its point beneath the first ring.
Sabine's good hand caught his wrist.
"Break the ring," she said. "Not the finger."
"I know the distinction."
The water climbed over Mara's boot tops. It smelled of old mortar, root rot and the faint metallic bitterness of a tank that had been scrubbed recently. Not clean. Prepared.
She raised the lamp toward the wall. The cistern was oval, brick-lined, with the flooded conduit behind them and a barred draw-off channel opposite. The roots had entered through cracked mortar around the channel and thickened there, fed by decades of leakage. Fresh scratches shone on the iron bars.
Not rust. Tools.
"They tested the grate," Mara said.
Teren looked across the water. "Can it be opened?"
"Everything can be opened. The useful question is what it kills while opening."
Ivo snapped the first ring with a twist of his knife. Sabine made no sound. The second was heavier, bearing the Veylan key and thorn. Ivo shifted his grip.
Behind them, boots scraped in the conduit.
"Lamp down," Teren said.
Mara lowered it before the next shot. The ball passed where the flame had been and struck the grate with a flat clang. Darkness swallowed the chamber except for the small yellow shield of her hand around the wick.
Teren took the lamp from her. He did not seize it by the handle, which was hot, or crowd her fingers and make her drop it. He slid his palm beneath the oil cup, used the uninjured side of his coat as a screen and held the flame exactly where she needed it.
He had watched her do that once in the lower works.
Mara hated that she noticed.
She waded to the grate. Six iron uprights had been leaded into stone. The Office scratches lay around the central pair, where someone had cleared scale from the joints. Beyond them, water moved through a low brick throat. Air touched her face from that direction, cold and resinous.
An outlet.
Also the place Pell expected them to go.
"Hold for Pell," she said. "Not hold the passage. Hold us."
Teren's silence changed shape.
Mara turned.
He still held the lamp steadily. Water ran from his hair to the collar of his torn coat. One sleeve was stiff with blood from the injury he had declined to discuss since the gate chamber. His eyes did not leave the grate.
"What?" she asked.
"There is a maintenance stair beyond it."
Ivo stopped working at the ring. "You know this cistern?"
"I know the survey description."
"No," Mara said. "You know which way the air goes."
Another scrape came from the conduit. A voice ordered someone to bring the firing rest forward.
Teren set the lamp on a projecting brick, safely above the water. Even now, carefully. He then took Sabine's good hand from Ivo's wrist and placed it against her own chest.
"Break it," he told Ivo.
The seal ring cracked under the knife hilt.
Sabine's face emptied. Ivo pulled the pieces free and pushed them into her palm.
Mara waited.
Teren rose. "Before the wedding journey, I made an arrangement with Pell."
The water slapped softly against the bricks.
"An arrangement," Mara said.
"If the convoy was attacked and the Office escort compromised, he was to take us through Veylan's lower waterworks. This cistern was the collection point."
Ivo gave one short laugh. "You gave a Crown investigator our enemy's drains."
"I gave him a route copied from a Rusk field ledger. I did not know it reached beneath the house."
Mara put her hand against the central bar. The iron was cold enough to ache through her skin.
"What did you receive?"
Teren looked at her then.
His elaborate words were gone. "Your life, if the marriage failed."
"You did not own it to bargain with."
"No."
That plain answer landed worse than a defense.
A musket barrel edged through the conduit opening behind them. Ivo caught it with both hands and drove it upward. The shot deafened the cistern. Flame flashed against the roof. He wrenched the barrel sideways until the man holding it cursed, but another pair of hands appeared behind the first.
"Work now," Ivo shouted. "Murder each other after."
Mara pulled the leather cartridge case from his belt.
"Empty."
"Paper too?"
He released one hand long enough to tear it free. Three bitten cartridges remained in the side pocket, each with a pinch of powder trapped in its fold.
Mara took them to the grate. The quantity would not burst an iron bar. It might crack old lead if she confined it tightly enough. Might also drive fragments back through Sabine, whose arm could not survive another shock.
Teren followed with the lamp.
"Tell me what to do."
"Remove your neckcloth."
He did, one-handed, without asking whether she meant to burn it. Fine linen. Dense weave. Expensive enough to take a fold without leaking powder.
She tore it into strips with Ivo's knife, packed the salvaged powder into the scraped joint and tamped it with wet thread pulled from her cuff. The water had nearly reached the joint. If it drowned the charge, they would have no second attempt.
Teren crouched beside her, shoulder between her and the conduit.
"Your bargain placed Pell here," she said.
"Yes."
"Say what you mean to call that."
A ball struck the brick above his back. He did not duck until the chips had passed.
"A mistake that may kill you."
"Better."
She twisted lamp lint around a sliver of cartridge paper. Teren shielded the work with both hands, making a small dry room around hers. His injured wrist shook. The flame did not.
That was the trouble with him. Not his courtesy, which could conceal a warrant as neatly as fear. It was the things he held steady after there was no advantage in being observed.
Mara lit the paper.
The improvised fuse hissed green at the wet edge.
"Down."
Teren covered Sabine. Mara plunged beneath the water beside them and pressed her palms over her ears.
The charge struck through the cistern like a hammer against a bell.
Water punched her flat. Light vanished. For a moment there was only pressure, bubbles and the taste of iron. Then a current seized her skirt and dragged her toward the grate.
The central bar had not broken. The lead around its foot had.
Mara surfaced coughing. Teren was already at the bar, levering it with Ivo's musket while Ivo fought to keep the weapon pointed away from the conduit hands. The stock cracked. The bar shifted the width of a thumb.
"Again," Mara said.
Teren changed his stance. His injured arm failed; his shoulder struck the wall.
Ivo abandoned the musket, planted one boot against the brick and hauled with him. The bar came loose at the foot. Water found the gap and screamed through it.
The upper socket tore free.
The current took the bar, the broken musket and the lamp. Teren caught the lamp by its wire guard before it vanished into the throat. Burning oil washed over his knuckles. He closed his hand around the guard and held on.
Mara stared at his blistering skin.
"Let it go."
"You need it."
"I need you able to climb."
His fingers opened. The lamp spun through the grate, flame guttering in its glass, and struck somewhere beyond with a sound of breaking metal. Darkness returned.
The gap was narrow. Mara forced herself through first. Brick scraped her ribs. The current pulled at her legs, trying to fold her beneath the low roof. She found the floor with one knee and reached back.
Ivo passed Sabine through.
Her ruined arm caught on the bent socket.
Sabine gasped once. Not loudly. Her good hand opened, and the broken pieces of her seal ring fell into the black water.
Mara caught one fragment against the bricks. The other vanished.
"Leave it," Sabine said through her teeth.
Mara closed her fist around the piece she had saved and pulled. Sabine came free with a wet tearing sound from beneath the bandages.
Teren entered last as Office men splashed into the cistern. A hand caught his boot. Ivo kicked past Mara's shoulder, heel striking knuckles. Teren crawled into the throat and Ivo rammed the loose bar crosswise behind him. It jammed against the brick, buying them the length of one breath, perhaps two.
They moved on hands and knees through water that ran faster with every yard. Mara kept one hand on Sabine's belt. Teren stayed behind Sabine, lifting her injured side whenever the channel narrowed. He did it with burned fingers and never once touched the arm itself.
The throat bent left.
Ahead, a dull amber light trembled across the water.
"Stair," Teren said.
Mara smelled the air before she saw it clearly. Lamp oil. Wet wool. The sweet medicinal edge of prepared sleep-smoke.
Pell had not merely known the outlet. He had furnished it.
Behind them, iron groaned as the Office men worked the bar loose.
Ahead, shadows crossed the amber light. Four men at least, standing where the brick throat opened beneath the maintenance stair.
Ivo drew his knife.
Sabine leaned against the wall, her useless hand dripping steadily into the current. "There should be another draw-off," she whispered. "For drought years."
Mara felt along the submerged brickwork. Smooth mortar. Smooth again. Then a vertical seam beneath a skin of lime.
A sealed door.
Teren crouched beside her. In the amber spill from Pell's lamps, his burned hand hovered near hers without closing over it.
"Can you open it?" he asked.
The men ahead began to lower their smoke pots.
Mara pressed her thumb into the seam. The lime crumbled, exposing fresh black pitch beneath.
Fresh enough to hold the print of a gloved finger.