Alice shut her ears to Aunt Edwina’s dreadful voice and followed Gavin down to the cracked and ruined basement. Her heart beat like a snare, and she was only vaguely aware that she had automatically grabbed her tools before jumping off Gavin’s ship. Simon and Glenda were on their hands and knees in the corridor, trying to make it to the stairs.

“Gavin!” Glenda slurred.

“Do you hate me that much?” Simon gasped.

Gavin’s lips tightened as he and Alice ran past. He called over his shoulder, “I’m sorry! We’re trying to help.”

“What are we doing?” Alice demanded.

“You’re some kind of clockworker, Alice,” he said.

The words slammed into her like stones. She’d been trying to forget. Her terror of the clockwork plague rushed back at her. Bad enough that Gavin was infected. Now she herself was somehow affected.

Gavin felt her stiffen. “You are! You’re not completely like other clockworkers, but you’re close. You know machinery. You can defuse the device.”

Alice wrestled with fear. “I don’t have a diagram!”

“You saw what Edwina did to it, and she used parts from your automaton. You can do this.”

“I don’t know if I can, Gavin. If I make a mistake, we’ll be dead.”

“And the alternative is?”

He pulled her into Edwina’s workroom, the one with the door blown inward. Wrecked equipment was scattered everywhere, and for a moment Alice was back in the basement of Edwina’s house, the one that had imploded. In the center of the floor crouched the malevolent brass spider, its claws sunk into the stone, and hunched over it was Lieutenant Phipps. She was trying to open it, without success.

“You!” Phipps barked, and launched herself straight at Gavin. She slammed him into the wall with her metal forearm across his throat. “I’ll tear your heart out!”

“Gavin!” Alice cried.

“The device!” Gavin choked. He twisted and managed to break away, but only because Phipps was still somewhat groggy from the pollen. She snapped a punch that caught him in the chest and knocked him backward. Alice felt the blow herself.

“You still fight like a pirate, boy,” Phipps snarled.

Gavin lashed out with a spin kick, but Phipps ducked beneath it. Her metal hand grabbed his ankle and wrenched him around. He landed on his back. “Alice! The device!”

Alice forced herself to ignore his pain and to turn to the spider. Automatically she unrolled the velvet cloth with its tools inside. Opening the access hatch was no trouble—it was the exact same hatch Edwina put on all her spiders.

“You have sixty seconds to evacuate,” boomed the spider in Edwina’s voice.

Another crash. Gavin had rolled aside just in time to avoid the heavy pestle Phipps tried to bring down on his head. He managed a one-two rabbit punch to her ribs, but the angle was bad and he didn’t do much damage. Phipps pointed her metal arm at him, palm out.

“You have fifty seconds to evacuate,” said the spider.

Alice stared at the machinery inside. It was all a complicated mass, and she understood none of it. The wheels and gears and delicate wires snapped with yellow sparks, and she was certain that if she made a mistake, she would die, or the device would detonate instantly.

“You have forty seconds to evacuate,” said the spider.

Gavin rolled to his feet just as a wire whipped out of Phipps’s palm and wrapped around him. He struggled, but his arms were pinned to his sides. Phipps flicked a knife from its sheath with her free hand and moved toward him. Alice snatched up a half-broken beaker and flung it at the back of Phipps’s neck. It scored a red wound.

“You have thirty seconds to evacuate,” said the spider.

Phipps whirled, eyes wild. “You snotty upper-class bitch! I’ll get you next!”

Gavin lurched into her from behind. They both went down, though Gavin, whose arms were still pinned, was at a clear disadvantage.

“The device!” he shouted again.

“You have twenty seconds to evacuate,” said the spider.

Alice forced herself to study the machinery. It still made no sense. She had no diagram and no instructions.

Did she need them?

But operating without them would mean . . . what? She wasn’t a clockworker—quite. She had been assembling machines for a dozen years, and clockworkers never lived longer than three.Alice had always assumed she was just talented. Theoretically, anyone could do what she did, with careful instructions and enough time. That no one had done it meant nothing. If Alice pulled this off, it would mean breaking more than mere societal rules. It would mean becoming truly unique. No rules need apply.

Phipps shoved Gavin aside and regained her feet. Alice swallowed. All right. She was unique. Machines answered her touch, and nothing could stop her. And with that thought, the memory of what Edwina had done to the spider came flooding back. She saw how everything fit together and, more importantly, how everything came apart.

Alice reached into the spider with a pair of forceps and extracted a single memory wheel. The yellow sparks died, and the spider released its grip on the cellar floor. Alice tossed the wheel away with a sigh, then stiffened as a cold steel touched her throat.

“Good work, Agent Michaels,” Phipps said in her ear. “That deserves a reward.”

“We’ve already released the cure,” Alice lied. “There’s no point in killing me.”

“There’s personal satisfaction.”

“I saved you just now.” Alice’s heart beat at the back of her throat. “I saved the entire Ward.”

“Susan!” Simon d’Arco was leaning against the doorjamb. “Susan, don’t! If she released the cure, there’s no point in killing her, and she just saved all our lives. Your life.”

Phipps turned her head only a little. “She committed treason. I’m just expediting the sentence.”

“A man gives in to anger,” Simon said. “What would an honorable Ad Hoc woman do?”

A long moment passed, and Alice prayed Phipps would believe the lie. Then the knife went away. Alice found she could breathe again. Gavin struggled out of the wire and sat up.

“You have until sunrise to run,” Phipps said. “Then God help you.”

“All right, Edwina,” she said, “it’s time to give the cure.”

“I don’t know why I would want to,” Edwina said peevishly. “You thoroughly wrecked my wonderful plan to destroy the Third Ward. What am I going to tell the other geniuses at parties? ‘My doomsday device almost went off. It almost destroyed an entire police force.’ I’ll be laughed out of society.”

“Don’t make me call Kemp on you,” Alice warned.

“Madam?”

“Oh, very well,” Edwina sighed. She was holding a large glass jar, and Alice wondered where she’d gotten it. “Set the ship to hover, Gavin, if I may use your Christian name.” Gavin obeyed while Edwina set the jar down and took up the spider Alice had snatched from the Doomsday Vault, the one with the hollow tubules running up and down it. “Your left arm, please, Alice.”

“Why?” Alice asked suspiciously.

“Because your one true love can’t administer the cure to himself, and I need to show you how to do it.”

Alice held out her left arm, and Edwina fit the spider around it. Dr. Clef stepped forward with unabashed curiosity. Kemp stood behind Alice, still uncertain what his role in all this was. Alice had banished the little automatons belowdecks for fear they might get swept overboard or otherwise lost. Click stood on his hind legs and peered over the gunwale, intent on something that interested only him. He popped his phosphorescent eyes alight to see better.

The spider moved cold and heavy against Alice’s skin. Its legs wrapped around her forearm, and its body flattened against the back of her hand, forming a sort of gauntlet that left Alice’s palm bare. It also put little claws at the end of each finger. A quick pain pierced her arm, and Alice yelped. The tubules ran red with her blood. Instantly, Gavin was at her side.

“What have you done?” he barked.

“Don’t strain yourself, darling. Everything is going according to plan. The spider creates a curative serum from her blood. It’s quite harmless, though the spider will never come off. It’s quite fashionable, don’t you think? Much better than a corset.”

“What do you mean it won’t come off?” Alice shook her hand, then pulled at the spider, but it clung like a tiny demon. Gavin pulled at it as well, but to no avail. The spider’s eyes glowed scarlet.

“If you’re finished fiddling,” Edwina said, “we can get on. The spider’s eyes glow red when it touches someone who’s infected with the plague. You’re touching Gavin now. Scratch or poke him with the claws to inject the serum. The lights will then glow green to indicate that it worked. Go ahead—you’ve earned it.”

Gavin silently held out his arm. Alice set her mouth. If this was what it took to cure Gavin, she would do it without complaining. She took a tentative swipe at him, but failed to pierce the skin. Gavin flinched, then held himself more firm.

“Don’t be shy,” Edwina instructed. “You’re saving his life.”

“You endangered it,” Alice retorted, and swiped harder with her new claws. This time she drew blood, four parallel scratches on the inside of Gavin’s forearm. The claws sprayed a bit of bloody serum over the wounds. Gavin winced but held firm.

“That should do it,” Edwina said. “Kemp, let us know when sixty seconds have passed.”

“Yes, miss,” Kemp said.

Edwina arched an eyebrow. “What happened to Madam?”

“Madam is currently occupied with Sir,” Kemp said.

“Ah.” Edwina actually looked flustered and a bit disappointed. “Yes.”

The longest minute of Alice’s life passed. She looked at Gavin, his blue eyes and silver-blond hair lit by the dim light of his new airship. He managed a smile, and suddenly she was glad to be here on this ship, as long as he was here.

When Kemp announced the minute was over, Alice grabbed his hand with her new gauntlet. Everyone looked at it.

The spider’s eyes glowed red.

“Wait a moment,” Edwina said. “Wait.”

Alice held her breath. Everyone watched. Even Click turned his head. But the lights glowed red. A ball of hot lead formed in Alice’s stomach, and Gavin’s face went still as a block of ice.

“I don’t understand it,” Edwina said. “The cure works. I know it works. I tested it extensively. Why . . . ?” Her expression changed. “Oh! Oh dear. There’s some bad luck.”

Alice rounded on her. “What are you talking about? What do you—?” And then Alice knew. She turned back to Gavin and saw the same realization in his eyes. The strength of it rushed at her with a physical force and drove her to her knees. Gavin went to the deck with her.

“You babbled at the symphony,” Alice said. “About math and the universe. I thought you’d gone mad.”

“I couldn’t stop myself,” he whispered. “I didn’t know why. And the Jupiter Symphony swept me away until Simon snapped me out of it. I was born with perfect pitch, so no one thought of that as a symptom.”

“Increased physical coordination,” Alice said. “Going for days without sleep. Building an airship that not even Doctor Clef would have considered. It was all there.”

“I’m sorry,” Edwina said again. “I didn’t mean to make you into one of us.”

Alice was crying again. “Cure him! You said you can cure him!”

“I can’t cure people like us.”

“Say it!” Alice grabbed Edwina by the collar and shook her like a rag doll. “Say the damned word!”

Edwina whispered, “I can’t cure a clockworker.”

Alice let her go and ran back to Gavin. The world was swallowing her up, crushing her between stones. Gavin had been infected for a year. He might live another year, if they were lucky. Or he might go mad tomorrow.

“I won’t,” she sobbed, running her hands over Gavin’s face. He took her fingers and kissed them. “I won’t watch it again, Gavin.”

“I won’t die,” he said. “Not yet.”

Edwina stepped forward with the jar. “We need to release the other cure, Alice. You need to release it.”

“And how do I do that?” Alice felt drained.

“I have finished incubating it.” Edwina tapped her own chest. “Here. Where no one would look for it, just as I told you.”

She handed the jar to Gavin, who kept his free arm around Alice. “What’s this for?”

“You’ll see in a moment. That’s more warning than Pandora had.”

“I don’t understand. If the cure is inside you, how can it help anyone else?”

“I gave Alice the means to release it, darling.” Edwina glanced meaningfully at the metal gauntlet. “That’s the final stage.”

Alice held up her metal-encased hand. The claws gleamed like knives in the blue light. “No. No, Edwina. I never want to see you again. But I’m not going to—”

“Darling, please! I’m so tired.” Edwina passed a hand over her face. “I’ve been holding the plague at arm’s length longer than anyone else in the world, but I’m starting to lose. I can feel my mind slipping. Please, darling. Destroy England, and save the world.”

“Why must it be both?” Alice cried. “Why is it everything or nothing?”

“I’ll ask God when I see him.” Edwina spread her arms and raised her chin.

Alice, pale and trembling, stood before her aunt and thought of the thousands of children dying of plague below their feet. She thought of her father and mother and brother. She thought of the way Edwina had manipulated her from childhood, of how she had signed Gavin’s death warrant. With a low scream, she raised her left hand. The claws glittered. Edwina held her breath. Alice pulled her hand back—

And dropped it.

“I can’t,” she whispered. “Not even to save the world.”

And then Gavin was behind her. He took her gloved hand in hers and raised it again. “All right?” he said.

Alice bit her lip and nodded. Her gaze met Edwina’s, and Edwina shut her eyes, her arms still spread. Together, Gavin and Alice pulled her hand back, and together they slashed down.

Edwina’s clothing and flesh parted like a ripe strawberry. A dark and terrible gash opened up, and Edwina fell backward onto the deck. She thrashed and convulsed. From the wound poured not blood as Alice expected, but millions of insects. They buzzed upward in a cloud, their tiny bodies blinking phosphorescent green.

“Fireflies,” Gavin said in his hoarse voice.

“The jar!” Dr. Clef shouted.

Gavin reacted. He swept the open jar through the cloud and caught a small section of the cloud inside the glass, then clapped on the lid. They flitted around inside.

Click batted at some of the free-flying ones, then backed away, back arched. Dr. Clef slapped his arm. “Ouch!” he said. “They bite!”

“It’s how they spread the cure,” Alice said. “And each person they bite will spread it to other people when he coughs or sneezes, until the cure goes through the whole world. A disease to cure a plague. It just doesn’t work on clockworkers.”

Gavin held up the jar. “Why did she want us to keep some?”

“So we can take them to Europe and elsewhere, I think,” Alice said. “It’ll spread the cure faster.”

Edwina’s body fell still. It lay, small and shriveled, on the deck. Alice knelt by her as the fireflies descended into London. For better or worse, this single woman had just changed the entire world, and no one would ever know who she was. Alice tried to close Edwina’s empty, staring eyes, but they remained stubbornly open. A piece of canvas descended to cover the body.

“I hope Madam doesn’t mind,” Kemp said.

“Thank you, Kemp,” Alice told him. “You always know what to do.”

“Madam,” Kemp said.

Gavin took up his place at the helm again. “Where should we go?”

“China,” Alice said. “We need to go to China.”

The propellers started up again, and the airship glided forward. “Why China?”

“Phipps said the cure had been discovered and suppressed more than once, and China has its own clockworkers—Dragon Men. They may have a cure for clockworkers.” She managed a smile, though it came out sickly. “We must remain optimistic.”

“I can do that,” Gavin said, “if I’m with you.”

“How will we go to China?” Dr. Clef asked. “I do not think even I can learn Chinese so quickly.”

“We have a friend.” Gavin produced the silver nightingale from his pocket. “Feng Lung was the last person to touch this besides me. I hope it works.” He pressed the bird’s left eye. “Ambassador Lung and Feng Lung, this is an emergency. I need to invoke the favor you owe me. Meet us where Feng Lung and I first became friends.”

Gavin tossed the nightingale into the air. The tiny messenger angel fluttered its wings and skimmed away.

They were standing at the crossed pathways where Gavin had first rescued Feng from trouble all those months ago. Alice and Gavin faced Jun and Feng while Kemp busied himself with a shovel near Edwina’s canvas-wrapped body. For once, he didn’t complain. Click stayed on the airship, which had landed on a nearby field. Dr. Clef stood a few feet away, clutching the sack he had salvaged from the Third Ward. He had offered to stay on the ship as well, but Alice didn’t trust him enough to leave him alone. Night was lifting like raven wings, revealing soft light beneath. The chilly air rang with traffic sounds from the distance. London was nearly awake.

“What kind of problem, sir?” Alice asked.

“I have come to the regretful conclusion that my eldest son is unsuited for statecraft.” Jun bowed his head briefly, his hands folded within his sleeves. “He is talented at language, but often fails to choose his words wisely.”

“My father is correct,” Feng said without a trace of embarrassment. “I would start a war between our countries.”

“So you would like us to escort him home,” Gavin said.

“Precisely.” Feng winced and slapped his neck. A bit of green came away on his fingers. “I do not remember London suffering from biting insects at this time of year. Is this normal?”

“We would be pleased to take Feng home, Ambassador,” Alice said, ignoring the question. “Can he leave—”

“Immediately, yes,” the ambassador said. “I believe certain people of ill repute are already seeking him, and diplomatic immunity would not be helpful.”

“We should go ourselves,” Alice said. “I’m sure Phipps is rallying the Third Ward to look for us once the sun rises, and it’s still dark enough for plague zombies to—”

“Look!” Dr. Clef pointed.

Half a dozen plague zombies, possibly those once controlled by Edwina, shambled toward them over the grass. Their arms were outstretched, and thin skin hung in tatters ragged as their clothes. One of them was a child, perhaps six or seven years old. Alice and the others backed away, toward the ship. Then the first bright beams of sunlight came over the horizon and struck the zombies full on. They flinched, but, instead of fleeing for the shadows, they stopped. Identical looks of wonder crossed their mottled faces as the sun slipped gold slowly over their bodies and faces. They faced the dawn and let the light wash over them. Even as Alice watched, some of their sores stopped weeping, and their bloody tears ceased. The child jumped once, then twice. Then he smiled.

“It’s working,” Alice whispered. “Oh, Aunt Edwina! Oh, Father! It’s working!” She hugged Gavin, who whirled her around with giddy joy. “It’s working!”

“I do not understand,” Feng said. “What is working?”

Tears were streaming down Alice’s face. “I didn’t think I could be happy again, but I am! Can you forgive me, Gavin?”

“What for?” he asked, laughing.

“For being happy, even when you’re . . .”

“Sick? Alice, I never want you to feel sad or guilty. I love you always.” He kissed her. “Let’s fly.”

A hatch opened, and Dr. Clef climbed out with a machine under one arm. He stumped over to Gavin and pushed his goggles up to his forehead in a way that reminded Gavin of Old Graf.

“That workshop you have below is primitive and dreadful,” he spat. “How am I going to re-create my poor Impossible Cube without a decent laboratory?”

“You’re lucky to have a laboratory at all, Doctor,” Gavin pointed out. “What is that?”

“My first attempt. I have tried to find ways to stretch across to other universes to find my cube, but all I did was reach back to old hypermagnetic frequencies. Look at this nonsense.”

He twisted dials on the machine. Two parabolic reflectors spun, and a square of glass lit up. The machine made eerie pinging noises, and bits of light danced across the glass.

“What am I looking at?” Gavin said.

“Sources of power for automatic machinery,” Dr. Clef said impatiently. “You see? This one is Kemp. It is very close. And this tiny one is the clicky kitty.”

“What’s this one?” Gavin pointed. “It’s a different color.”

“That one has a different power source than the others.”

Gavin studied the glass a moment. His brow furrowed. “Is it . . . following us?”

“Yes, of course.”

The connection clicked instantly, and a feeling of dread came over Gavin. He knew the answer, but he had to ask the question anyway. “Why is it a different power source?”

“This kind of machinery demands it. It is what happens when one grafts machine parts to human flesh.”

“Like the machine parts grafted to Susan Phipps?”

“Yes, exactly.”

Dr. Clef shut off his machine, and Gavin pushed the Lady’s engines harder, speeding them toward the Orient.