"I don't know."
  "Some other world?" Smith persisted. "How can they materialise and dematerialise like this? Are they even real?"
  "The destruction they cause is real enough."
  "And they seemâ¦" Smith hesitated. The baruch-landau, like an elderly assassin, puffing hard, was approaching the Eiffel Tower at last. It was quieter here, the machines had moved across the city. "Old," he said, with a note of wonder.
  "What?" Van Helsing shouted. Smith swerved to avoid the corpse of a donkey lying in the street. It was quiet now on the Champ de Mars:
  A long avenue of fantastical shapes, wizened four-armed creatures, semi-human, semi-ape, standing guard, carved in stoneâ
  Landscaped canals, built to reflect what could be seen on the surface of the planet Mars, a silver gondola, used to carry tourists, now upturned in the water. A giant model of the red planet itself had fallen off its dais and cracked, and Smith had to swerve around it. Groaning, the baruch-landau came to a halt.
  "We're out of coal," Van Helsing said, apologetically.
  But it had lasted them long enough. Smith jumped off the vehicle with a groan of his own â his relief echoed in the machine's own creaks and groans. Van Helsing climbed down and joined him. It was eerily quiet. They stood on the red surface of the Champs de Mars, the Tour Eiffel rising above them like a pointing finger. Above it the stars shone down, the Milky Way traversing the dome of the sky. Somewhere up there was Mars itself, surrounded by its two moonsâ
  Which, down here, were still on their pedestals, smooth round globes showing a lack of imagination, Smith thought, on the part of their anonymous sculptor.
  "Why old?" Van Helsing said.
  Smith couldn't answer him. He had imagined the threat from space to be something ill-defined, a technology so advanced it could remake human minds and shape whole planets. These machines, walking oddly over the Parisian cityscape, giant metal tripods spewing fire, flickering in and out of existence, seemed somehow to belong to a sideways world, conjured out of some alternate realityâ
  "Could we have built them?" he said to Van Helsing.
  "The machines?"
  "Yes."
  "The technology involved⦠Oh." Van Helsing's eyes clouded and he said, "I see what you mean."
  "Could they be Babbage's?"
  "I find that unlikely. In any case, I have never heard of such war machines being designed, let alone constructed," Van Helsing said.
  "But it is not impossible."
  "But the device," Van Helsing said. "It is clearly extraterrestrial."
  "But are those machinesâ" Smith shrugged. For the moment it didn't matter. They were talking because talking was better for the moment than acting, because in a moment they would have to press on and, the truth be told, he was exhausted.
  The words of a long-ago instructor at the Ham facility came back to him.
In every mission there comes a moment of near-breaking, the moment when you want to stop, to abandon the mission, to find a hole and crawl into it and sleep, forever. At those moments, stop. Give your mind and your body the time to catch up, even if the mission reaches a critical stage. You are no use to anyone at that stage. Take a break. Look back at how far you've come, and evaluate clearly how far you still have to go. Only then, act.
  It was quiet at the Champs de Mars, and in the distance the machines moved, the city burned, in the distance Charles Babbage sat in his dark castle and planned his dark plans, the Mechanical Turk was deactivated and dumped in storage, Alice was dead, the Harvester was moving, Mycroft's long-laid plans were forming or unravelling, he didn't know. He looked up at the tower rising above them, a graceful latticework of iron, worked by humans, two airships moored to its top. "What's up there?" he said, looking at it again, uneasily. There had been rumours at the Bureauâ¦
  Van Helsing said, "Nothing much, I imagine. There had been restaurants during the Exposition Universelle, and a viewing deck."
  "And now?"
  Van Helsing shrugged.
  Smith shook his head, feeling uneasy. It was too quiet at the Champs de Mars, almost as though, somewhere, unseen eyes were watching them, and calculating⦠He took a deep breath, stretched aching muscles.
  "How do we get up there?" he said at last, resigned.
  "There's a lift," Van Helsing said.
  Smith said, "Oh."
Â
They found an opening at the foot of the tower. A lift, or â in the parlance of English-speaking Vespuccians, an elevator â apparently functional, and with a small, utilitarian sign on it of a skull and crossbones accompanied by the words
Entry Forbidden. Biohazard
in French.
  "What do you think?" Smith said. Van Helsing shrugged and pulled off the sign.
  The lift took them up, smoothly and without a fuss, travelling through latticework up to the second level of the Tour Eiffel. There the doors opened noiselessly and they stepped out onto what appeared to be an abandoned viewing deckâ
  Shadows moving up there, a silhouette momentarily seen against the burning skyline, something feral andâ
  A shot rang out. Smith hit the floor, his own gun out, the shadow moved again and he fired, once, twice, and it fell, tumbling over the parapet in silence.
  Smith swore. Why had he assumed the tower would be empty? He turned to Van Helsingâ
  And saw the other man slumped on the floor, blood spreading across his chest. "No," Smith said. "Abraham, noâ¦"
  "They got me, Smith," Van Helsing said. His voice was thick, surprised. He put his hand to his chest. It came away bloodied. He stared at it, confused. "They got me," he said, wonderingly.
  "Let me see it, Abraham."
  Smith reached for the other man, cut out his shirt. Shadows moving in the distance, coming closer. When he tore open Van Helsing's shirt the bullet hole was marked. Van Helsing coughed, and blood bubbled out of his mouth and fell down his chin.
  "Let it go, Smith," Van Helsing said. He smiled, or tried to. "Isn't this the way we always thought we'd go? Better than to lie in bed, riddled by cancers, or old age, or that sickness that eats away memory. I wanted one more job."
  "You had it," Smith said, and his own voice was thick.
  "Go up to the top of the tower. There are⦠machines there. Be⦠careful."
  "Abrahamâ"
  But his friend was sinking to the ground, his eyes fighting to stay open. Smith held him, cradling him in his arms, Van Helsing's blood seeping into his own clothes. "It was worth it," Van Helsing said. "Playing⦠the Great Game."
  His eyes closed. His breathing stopped. Gently, Smith lowered him to the ground. Abraham Van Helsing, another name added to the tally of the dead. Shadows moved, coming closer, snarling. Smith's gun was out of its holster and he fired, and watched them drop.
  What the hell
lived
up here? he thought.
Â
He examined the first body. His bullet had hit it in the chest, it was still alive. It would have been human, butâ¦
  What
were
those things?
  The sign on the lift door.
Biohazard.
  What use was the tower being put to?
  The creature would have been human but it was changed in some grotesque way. Not the way of the F-J serum, nor in a Moreau-style hybridisation (Smith had the unfortunate experience of meeting that exiled scientist once), not even in the bizarre methodology of that mad hunchback genius Ignacio Narbondo.
  The body below twitched and foam came out of its mouth and still it tried to move, to bite him, with shiny yellow teeth. Its eyes, too, were yellow, and it was hairy, with a naked chest. Somewhere, a bell
dinged
, faintly but unmistakablyâ¦
  Smith went around the foaming man-dog creature and went to the parapet and looked out over the city. Paris, in flames â but the machines were moving, heading⦠east?
  And now he could see the circle of influence, just as Van Helsing had said it would be. The machines were moving in a radius of about three miles, a hovering shape of fire and smoke moving slowly but inexorably over the Parisian skyline. A baleful moon glared down, and above, the stars were being stubbed out as the smoke rose to obscure them.
  The device, he thought, would be at the centre of it. And moving. Somehow, it had opened a hole into â what? Another world? â and brought these machines of death and destruction into life.
  Get hold of the device, he thought. Shut it down.
  How?
  Van Helsing wanted him to go to the top of the tower. An aerial experimentation station, he had said.
  Perhaps he could get hold of an airship orâ
  Somewhere, the
ding
of a bell, faint but clearâ
  Smith turnedâ
  There were three of them, standing there. Hair grew out of their faces, spilling down. Their eyes were yellow, rabid. Their fingers curved into talons, their nails like scimitars. One of them growled.
  It had occurred to him, too late, that he should have made a start going up sooner.
  There were no lifts to the top of the tower.
  And the three creatures were blocking the stairsâ¦
  "I don't want to kill you," he said. He disliked guns and using them. And these creatures seemed to him somehow innocent, as if a great wrong had been done to them. They looked insane, they belonged at an asylum.
  "Step out of my way and you won't be hurt," he said.
  Somewhere, the ding of a bell, clear and loud, and for the third timeâ
  The three â men-dogs? What could you call them? â twitched as one, as if the bell was controlling their actions. Then they charged Smith.
  He dropped the first one with a shot but then a second barrelled into him and the gun flew, over the parapet and down, onto the Champs de Mars far below. Smith grunted, the air knocked out of him, and fell backâ
  His hand reaching for the knife strapped to his ankle, the blade flashing, and he buried it in the belly of the creature, who howled pitifully and collapsed on top of Smith, pinning him down. Smith, grunting, pushed at the body, the blood, the colour of pus, slipping into his clothesâ
  The creature was heavy and the third one was coming at him at an odd loping gait, teeth flashingâ
  Smith struggled to push off the body lying on top of him but couldn't. The dog-man came closer and his muzzle came down, bitingâ
  Smith shielded himself with the dead one on top of him and the living dog-man bit its comrade instead. Snarling, it tore at the flesh, pulling it, until Smith, with a sigh, managed to slide from underneath it. He rose to his feet, shaky, the bloodied knife in his handâ¦
  The dog-man stared at him over the corpse of its friend, an arm between its teethâ
  "Shoo," Smith said. "Shoo!"
  The dog-man growled.
  Smith, moving carefully, circled around the body. The dogman followed. "I just want to get to the stairs," Smith said. "Do you understand? I mean you no harmâ"
  Which was an unlikely thing to say, under the circumstances.
  The dog-man growled. He looked like he was thinking. Smith moved, his back to the stairs now; the way was open, he was going to make a run for itâ
  The sound of a bell, clearly and sweetly in the night.
  "Not
again
," Smith said.
  There came a growling sound around the corner and, for a moment, it felt to Smith as if that entire edifice, that Tour Eiffel, was shaking with it. He heard the pounding of heavy bodies and the unmistakable sound of gunshots, like the one that had dropped Van Helsing and he thought, There must be others up here, soldiers orâ
  He ran for it.
  Up the stairs, but now there were bodies coming at him from above, too, dog-men of sorts, hypnotised by that deadly sound of a bell, ringingâ
  It reminded him of something, rumours long ago, at the Bureau, and a failed mission on the Black Seaâ
  He twisted sideways, his knife flashed and a howling dog-man flew through the air and beyond the parapet and down to his death, the Champs de Mars, Smith thought, turning as red as the planet it was mimicking. Up the stairs and his knees hurt and it was a long way up, a longâ
  That damn bell, and now footsteps on the landing he had come to, the city down below, the tripods moving jerkily across the ancient buildings, the fires burning, that Egyptian obelisk looted from Luxor toppled, flames above the Louvre, hordes of people running down the Avenue des Champs-Elyseesâ
  Footsteps, and a voice like a bell saying, "You should not have come up hereâ"
  Smith, stopping, out of breathâ
  A man in his fifties, white in his beard, deep-set eyesâ
  That mission on the Black Sea, long ago, and a promising young Russian scientist, doing strange experiments onâ
  Dogs, yesâ
  An extraction that didn't work because the French, as it turned out, had got to him firstâ
  "Ivan Pavlov," Smith said, stopping still.
  That damn bell.
  He should have known.
Â
Â
FORTY-ONE
Â
Â
Â
Was it a sickness of the age, or of its sciences? Did it drive its practitioners mad, or were they mad to begin with?
  You had to be a little crazy, Smith always reasoned, to delve into life's bigger questions, to ask â
why are we here
? or,
what happens when I do this?
or
why is a raven like a writing desk?