Al-Noor was aiming a large pistol at Alice across the ruins of a dinner table while two of a group of squid men held a struggling Phipps. The dead squid man on the floor barely registered. A red haze descended over Gavin. The man had threatened Alice. With a snarl, Gavin launched himself at al-Noor. Al-Noor saw him coming. He flicked the pistol around to orient on Gavin and pulled the trigger. Alice screamed. The universe slowed down. Air became fluid as water. His body floated in it. He calculated how fast he was moving, the arc of his travel. He was aware of the temperature heating the barrel of the pistol and how brass and glass expanded with tiny crackling noises. He saw where the pistol barrel was pointed and in a fraction of a second assessed the eventual path of the emerging energy. In midair, his plague-enhanced reflexes lined up the Impossible Cube to match it. A yellow lightning bolt cracked from the pistol, crawled slowly through the air, and struck the Impossible Cube. The Cube sucked the bolt down, and the energy vanished.
The universe snapped back to normal speed. Gavin slammed into al-Noor. Both pistol and Cube went flying. The glass parts of the pistol shattered, but the Cube bounced, unharmed. Both clockworkers rolled across the floor, trading and blocking blows so fast, their hands blurred. Gavin was younger and stronger, but he was hampered by his wings, and al-Noor had the advantage of height and a longer reach. Any thought of plan or strategy fled Gavin’s mind. He didn’t feel any of the hits that landed. Nothing but the animal fury burned in him. Al-Noor’s face was twisted in an equally horrible rictus of rage.
“Sing, damn it!”
“Sing what?”
“Any note! Just sing!”
Gavin remained only vaguely aware of the two female voices speaking somewhere behind him. Al-Noor flicked a fist through Gavin’s defenses and caught Gavin on the chin hard enough to make him see stars. Gavin kneed al-Noor in the belly. Fetid air rushed out of him. Al-Noor straightened his right hand, and a needle sprang from his index fingernail. A clear liquid glistened at the pointed tip. He tried to stab Gavin’s face, but Gavin caught his wrist. The older man forced his hand inward, pressing his weight into Gavin, shoving the needle closer to Gavin’s eye. Gavin gritted his teeth and fought back, but al-Noor had the advantage now. The needle crept toward Gavin’s eye, and the light glittered hard and sharp off the tip. It brushed his eyelashes.
A terrible sound smashed through Gavin’s head. The needle jerked back. Al-Noor and Gavin both screamed and clapped their hands over their ears. The sound tore through Gavin’s mind. It was worse than countless claws screeching across a blackboard the size of a galaxy, and he felt as if his nerves were sizzling in acid. A part of him recognized the horrible noise as a tritone-two notes separated by three full steps. The two notes that made up the tone vibrated against each other at a ratio of one to the square root of two, an irrational, impossible number that couldn’t exist. Like all clockworkers, Gavin had perfect pitch, and the tritone, the idea of the tritone, spun him around, threatened to swallow him in the same way that infinite swallowed a whole number. He screamed and tried to shut the sound out, but his hands couldn’t quite mask it. Al-Noor writhed on the floor beside him, and Gavin was dimly aware that all the squid men had fallen to the floor as well.
And then the sound stopped. The pain ended, but the disorientation continued. Hands hauled him to his feet.
“How did you do that?” he gasped.
“I may not have perfect pitch,” Phipps said in his ear, “but after twenty-five years in the Third Ward, I can make a tritone with any note you-or Alice-can sing. Now, let’s get out of here before al-Noor and his squid men recover.”
“I’m so sorry we had to do that,” Alice said in his other ear as they stumbled toward the doorway. “Are you all right?”
“I–I think so.” Gavin shook off the disorientation and regained enough presence of mind to snatch up the Impossible Cube. It glowed pure azure, and it squirmed in his hands. The lattices twisted in ways he had never seen before, moving over and behind themselves, and his own hands seemed both close and far away at the same time. When he moved forward with Alice and Phipps, he could feel it tugging in his grip like a dog that wanted off its leash.
“The Cube,” he said. “It took in a lot of strange energy. I don’t know what that means.”
Phipps glanced back at the room. The squid men, who were plague zombies in their own way and who were also flattened by tritones, were stirring. Al-Noor was sitting up, his heavy belt askew and his black bathing costume torn. “Unless we want to kill them,” Phipps said, “we need to run now and worry about the Cube later.”
They ran. Phipps, whose monocle let her see best in the dim light, led the way. Alice noted the shattered doors they passed. “Good heavens, darling. Did you-?”
“Yeah.” The rage rose at the memory, and he forced it back down. “I’d do it again. Did he hurt you?”
“No, though he planned to. Your timing was perfect.”
The tunnel opened up into the enormous cavern. Most of the floor was taken up with the ocean, with a rim that ran around the edge. The Lady was moored to the quay, her envelope glowing softly, and he heaved a sigh of relief that she was still there. Bright sunlight outdoors made the mouth of the cave painful to look at.
They hurried aboard the Lady. When they reached the helm, the Impossible Cube twisted almost painfully in Gavin’s hands and began to pulse in colors: red, orange, yellow.
“What is it doing?” Alice asked, unmooring the lines. Her little automatons streamed out of a hatchway to flitter and skitter in a brass cloud around her.
“No idea.” Gavin held up the Cube. The lattices slid and twisted around so fast, he couldn’t watch them. It was like looking at the sun. “It feels like it’s going to go off or something, but I don’t know what to do about it.”
“Are we cast off?” Phipps threw switches on the generator, and it rumbled to full power. Electricity scrambled up the wires to feed the endoskeleton, which came to blue life. Gavin set the Cube down and took the helm. The Lady shuddered once and rose gracefully toward the cavern ceiling, streaming water from her lower hull. The nacelles were unaffected by their seawater bath, and Gavin spun the helm, pointing her toward the mouth of the cave and freedom. The Cube pulsed green.
“No!” Al-Noor was standing on the quay, alone. His cloak was missing, his hair rumpled, his silly swimsuit still torn. His belt was crooked. “Return at once! I will have the reward! I will!”
The rage threatened again, but Gavin still kept it under control. Al-Noor had no weapons in his hands and was no threat. The plague would kill him in a few months. No point in risking Alice’s life over further retaliation. Gavin spun the dial that cranked up the power to the nacelles and felt the Lady thrum forward. She skimmed toward the cave opening. Gavin felt himself relax a little. Alice was unhurt, and soon they’d be in open air again, on their way toward China. The Cube pulsed blue, then indigo.
“What’s the bloody Cube doing?” Phipps called.