Crawford eventually settled on one of the short blades in Trelawny's bone-handled pocketknife, and when Johanna had lit a candle and brought it to the table, he held the blade in the flame.

"Open your shirt and lie down across the table," he told Trelawny. His eyes were stinging from not having slept last night, and he squeezed them shut and then opened them wide; he looked at his hands and was reassured to see that they were not trembling.

The old man took his shirt off, exposing a broad chest matted with white hair and shoulders still corded with muscle. He touched a spot on his throat just above his collarbone, on the left side. "Here's your target, Doctor."

The lump did appear to be firmly stuck in place, very close to the jugular vein.

Crawford took off his coat and rolled his sleeves up past the elbow. "Pour a lot of brandy over my hands," he told Johanna, "and then soak a towel in it and - "

" - Scrub where you're going to cut," said Johanna.

"That's it." He looked up at Trelawny's drawn face. "I'd really like to get some ether. This is likely to hurt quite a bit."

"I don't mind hurt," said the old man through his teeth. "Me and hurt go way back."

Crawford shook his head. "As you please. Just, whatever you do, don't twitch."

When Crawford had rubbed his hands in the sluicing brandy and Johanna had swabbed the old man's throat with the soaked towel, Crawford held the lump in Trelawny's throat with his left hand and reached out with the knife in his right -

- and the blade stopped abruptly, two inches above Trelawny's skin, and would move no closer.

Peripherally Crawford noticed that Trelawny's face was slicked with sweat.

The heady smell of brandy was overpowering. Crawford carefully increased the pressure against the invisible barrier, not wanting to spear the old man if it were suddenly to relent - but the blade simply skittered aside; as if, it occurred to him, he had tried to push it through Chichuwee's invisible pot.

"The blade," he said in a strained voice, "won't get close to your throat."

For a moment the old man just breathed in and out. Then he whispered, "Infirm of purpose, give me the pocketknife," and took it from Crawford's hand.

The blade was steady in Trelawny's hand as he pressed it to the base of his own throat, but again the metal was turned aside.

"What's this?" snapped the old man, sitting up and jabbing uselessly at his throat several more times. "I shave, sometimes!"

"Not with the intention of cutting the stone from your throat, though," said McKee. "The stone can evidently tell the difference."

Trelawny dropped the knife and it clattered on the floor.

"This is Polidori's protection," he said furiously. "It seems the Nephilim won't permit any human to cut the man who is the bridge between the species. But it shouldn't protect me from me; I'm not just any human." He glared around at the others. "I wouldn't have confessed my sins here if I'd thought I wasn't going to die."

He picked up his shirt - which had got liberally splashed with the brandy - and tugged it on.

His face was grim as he added, "It seems we must rescue my granddaughter by Maria's means."

"And who'll commit a murder?" asked Crawford.

"Oh, who was ever going to do it?" grated Trelawny. "It will be me. I've got so many mortal sins on my soul that one more won't matter. I really thought - "

He finished buttoning his shirt and tucked it into his trousers. "I really thought, there for a moment, that the universe was offering me a noble death. Expiation."

He walked to the stairs and was halfway up when he turned. "Come along, my sad crew - I've got an errand to run, and you've got to go roust Christina out of her nest."

THEY BORROWED HATS AND two coats from Trelawny before getting into a cab in front of his house, so Johanna had a black bowler hat that made her short brown hair stick out to the sides and McKee wore a straw boater with a flower-pattern ribbon, surely something left behind at Trelawny's by a guest. Crawford was wearing Trelawny's Inverness cape and a tall brown beaver hat that had probably been fashionable in 1830.

None of them made jokes about the hats on the ride east past Green Park and up the Mall to Charing Cross Road. Crawford held the bottle with the sea mouse bobbing in it, and he tried to project a mental apology to the ghost but got no sense of acknowledgment.

"We can't let - " he began finally as the cab started up Gower Street, but McKee and Johanna both interrupted him.

"Certainly not," said McKee.

"I could - " said Johanna, but Crawford waved her to silence.

"None of us," he said.

His wife and daughter both looked at him uncertainly.

"If - " Crawford said, pausing to look around to be sure the cab had four walls and a roof, "if Polidori appears in vulnerable human form even for a moment, we must try to kill him in that moment. We can't let poor old Trelawny commit a murder - nor participate in one ourselves."

Both women seemed to relax, cautiously, though their expressions were skeptical.

"We'll fail," said Johanna.

"We can jump into the river," said Crawford, "if we fail."

"We'd be safe then," Johanna agreed, "as long as we remembered not to come up for air."

For a minute or so no one spoke, and Crawford stared out the window at the passing pillars and the high neoclassical pediment of the British Museum. Fourteen years ago McKee had told him about her father taking her there when she was eleven and about her fear that she might be in the room full of Egyptian mummies when the General Resurrection occurred.

"Christina won't be happy to see us," said Johanna, bracing herself as the cab was steered into Torrington Place.

"I don't believe she's ever been happy to see us," said McKee. "And small wonder."

Christina's house had muslin sheets across the lower half of the front window to keep soot from blowing in, but above it Crawford saw the curtain twitch as he climbed down from the cab; he waved the bottle as a placating gesture before helping his wife and daughter down and paying the driver.

Christina herself opened the door when he knocked - she was wearing a plain black smock, and her dark and prematurely sagging face was stern.

Without a word she took the bottle from Crawford, held it up to the daylight, and then held it to her ear.

She sighed in evident relief. "Thank you. I'm sorry I can't invite you in, but we have plasterers due to repair the ceiling - "

"We contacted Maria," interrupted McKee. "Her ghost, that is. She told us how to banish your uncle."

Christina shivered as she hugged the bottle to her chest. "You - forced her?"

Johanna said, "Trelawny's fourteen-year-old granddaughter is somewhere out in the City with your uncle right now. It's a cold day, and it'll be a colder night."

Christina sighed, and the steam of her breath whisked away on the chilly breeze. "Come in then, you punishments for my sins."

She led them into the entry hall, where Crawford noticed Johanna's coat still hanging on a hook from last night; God only knew whose coat she had left at the Spotted Dog.

The parlor still smelled of garlic from the bottle Johanna had broken under the nose of the monstrous black-painted thing, and by the gray daylight filtering in through the lace curtains he could see the new cracks in the ceiling. Christina carefully set the bottle on the table, which had been righted.

Crawford said, "I'm sorry we left so abruptly last night - "

"Say calamitously," said Christina, nodding.

"At least," he went on, "the thing followed us out."

"Yes, it did," said Christina. "Mr. Trelawny shot it - it might be dead now."

"Much luck," murmured Johanna.

A housemaid appeared at an inner doorway, and Christina asked her to bring a pot of tea.

"What is the required sin?" she inquired with a brittle semblance of cheer after the housemaid had withdrawn. "The one Maria's method calls for."

Crawford didn't look at his two companions. "You need to let one of us cut you," he said, "so that you bleed, and then you must summon him, call for rescue - invite him back to you."

He hoped that was enough - she would surely balk at the proposed murder of a stranger.

He could see a strong pulse in Christina's throat. "I - " she said. "This hardly seems - how would this aid in banishing him?"

Crawford cleared his throat. "Maria believes he will then appear, wholly, in his vulnerable human form. You're a blood relative of his, in, er, several senses, and you might be able to forcibly hold him in that form - by mental effort - for at least a few seconds."

"So that you can kill him," said Christina softly, "with wooden stakes and silver bullets."

"And cremation," added Johanna.

"I - don't think I can do it," said Christina.

Maria's ghost had said, She would not want to do that, because she has always wanted to do that.

"We need you to try," Crawford said. "Trelawny's granddaughter needs you to try."

"I - well, it would indeed be a sin. Even for a praiseworthy purpose, to call up a devil - invoke his love for me - "

McKee cocked her head. "Sister Christina," she said, "do you mean it would be a betrayal of your uncle? Do you mean it would be wrong to trick him?"

Christina frowned and shook her head impatiently; and then she stopped.

"I," she whispered, almost wonderingly, "think I do mean that! God help me - "

McKee leaned forward. "You trick a rat when you put bait in a trap."

"You put it so elegantly." Christina sighed. "That will be all, Jane, thank you," she added to the housemaid who had brought in a tray and set it down on the table.

There were eight flat biscuits in a tray beside the teapot, and Crawford made himself ignore them. McKee and Johanna each grabbed two.

"When did you people last eat?" asked Christina in sudden concern.

"I had supper last night," admitted Crawford.

"About twenty-four hours, for me," said McKee, and Johanna nodded to indicate the same.

"Good heavens. I'll have Jane prepare sandwiches - "

"Sandwiches would be good," said Crawford. "We can eat them on the way to the boat."

"I don't understand," said Christina. "Boat? You're ... leaving the country?"

Johanna said, "It's a moored boat at the Queenhithe Stairs, by Southwark Bridge. I slept aboard it for a year or so, when I was a Mud Lark."

"It's where Trelawny wants to trap Polidori," said McKee. "And he wants to do it while it's daylight. It's cold out; you'll want to bundle up."

Christina lifted the teapot and filled one of the cups. "I think," she said as she picked it up in her shaking hand - and she took a careful sip before going on - "I must do as you say. I think I always knew the day would come when I must, for the sake of my soul, betray him."

There were tears in her eyes as she set the cup back down. It rattled against the saucer.

THEY ALL CLIMBED INTO a cab and took it to the river south of St. Paul's Cathedral, and in Upper Thames Street Johanna had the driver let them out at Bradburn Alley, by a row of tall brick warehouses just short of Queen Street.

"Better we approach along the river," she said as she and her mother helped Christina Rossetti down from the cab. They had eaten several cheese sandwiches on the ride and now brushed crumbs from their coats.

Stout wooden bridges connected the buildings on either side of the alley, and men leaned out of doorways high up in the walls and guided boxes and canvas sacks being raised and lowered on long ropes by pulleys. Crawford led the three women down the alley, around walls of stacked crates and casks, and several times waved them into recessed doorways when heavy-laden carts with chain traces creaked past behind horses in heavy leather collars. Smells of oranges and tobacco and quinine spiced the turbulent air.

At the far end of the alley they were out in the sea-scented wind, viewing the broad face of the river from an elevation only a few feet above the water, and out on the rippled expanse white sails and black smokestacks contrasted with the gray sky. Crawford helped Christina over a low wooden fence, which McKee stepped over and Johanna vaulted, and then they followed a set of narrow-gauge coal-wagon tracks that paralleled the shore, toward the northernmost arch of Southwark Bridge twenty yards ahead.

A chorus of shouts broke out in the alley behind them, and Crawford wondered if a broken pulley had dropped a load.

He was about to glance back when, ahead of him, Johanna jumped and nearly pitched off the tracks into a rowboat below.

She caught her balance and threw him a scared look.

"One wasp doesn't mean - " she began.

Two wasps buzzed between them, and Crawford heard McKee curse behind him.

He looked back at her. "You and Johanna run ahead to the boat," he said.

More shouting from the alley behind them was audible now over the wind in his face.

As McKee and Johanna sprinted away toward the shadows under the bridge, Crawford held Christina's elbow and tried to get her to move faster; finally he said, "Excuse me, it's an emergency," and picked her up in his arms and began striding between the coal-wagon tracks after his wife and daughter. He had to shake Christina's lavender-scented black veil away from his hat brim twice before she noticed and tucked it behind her head.