by Greg Egan
Sam replied with a tone of wary optimism, “And the ten grand they gave me for the restaurant? They don’t want it back?”
“Not as far as I know.” Natalie wracked her brain for another puppet test, but then she decided that she’d already heard proof enough: no one else on the planet could make it sound as if ten thousand dollars sunk into that grease-pit would more than compensate for any minor inconvenience the two of them might suffer along the way.
“I owe you, Nat,” Sam declared. He thought she was simply working off his debt – the way he’d mowed lawns as a kid, to pay for a neighbor’s window that one of his friends had broken. He’d taken the rap to spare the boy a thrashing from his drunken father.
“How’s your hand?” she asked.
He held it up; the bandage looked clean. “They’re giving me pain-killers and antibiotics. The food’s pretty good, and they let me watch TV.” He spread his hands in a gesture of contentment.
“So, three stars on Travel Adviser?”
Sam smiled. “I’d better let you get back to work.”
Natalie started with the easiest target. A man who lived alone, rarely visited by friends or lovers, he was expected to wake around seven o’clock on D-day morning and go jogging for an hour before breakfast. That would be the ideal time for the drones to break out of their hiding places in the spines of the first editions of Kasparov’s five-volume My Great Predecessors, which presumably had appeared at a seductively low price in the window of a local used book store. The fake wallet was concealed in one of the book’s covers, along with the sliver of whorled and ridged biomimetic polymer that would need to be applied to the real wallet. Thankfully, Natalie’s own predecessors had already done the work of programming the clog dance of drone against touch-screen that could mimic a human tapping out any sequence of characters on a virtual keyboard. The jobs they’d left for the pilots had been of an entirely different character.
The shelves in target A’s library were all spaced to allow for much taller books, leaving plenty of room for a pair of drones to slice into the wallet’s compartment, grab the hooks attached to the cargo, draw it out and fly six meters to deposit it temporarily in a poorly illuminated gap between a shelving unit and a table leg. The safe itself was in the library, and prior surveillance had shown that it was A’s habit to place his wallet on the table in question.
The distraction was to be a faucet in the kitchen, primed to fail and send water flooding into the sink at full pressure. The house was fitted with detectors for any ongoing radio traffic – the bugs that had collected the latest imagery had used multi-path optics, until a new sunshade had been fitted to a crucial window – but a single brief RF pulse from a drone to trigger the torrent would appear to the detectors’ software as no different from the sparking when a power plug was pulled from a socket.
What if target A broke his routine and did not go jogging? The emergence of the drones and the fake wallet’s extraction would not be noisy, so those stages could still proceed so long as the library itself was unoccupied. What if target A had an early visitor, or someone had spent the night? The drones would need to start listening for clues to the day’s activities well before seven. Loaded with neural-net templates that would allow them to recognize voices in general, doors opening and closing and footsteps receding and approaching, they ought to be able to determine whether or not it was safe to break out.
But the surveillance images that showed the five books neatly shelved were three weeks old; it was possible that they’d ended up strewn around the house, or piled on a table beneath other books and magazines. GPS wouldn’t work inside the building, but Natalie used a smattering of WiFi signal strengths collected in the past to equip the drones with a passable ability to determine their location, then added software to analyze the echo of an infrasound pulse, to help them anticipate any obstacles well before they’d broken out of their cardboard chrysalises.
The doors and windows – and even the roof space – were fitted with alarms, but target A had no motion sensors in the library that would scream blue murder every time a housefly crossed the room. Not even two houseflies carrying an object resembling a credit card.
Natalie put the pieces together then ran simulations, testing the software against hundreds of millions of permutations of all the contingencies she could think of: the placement of the books, which doors were open or closed, new developments in the target’s love life, and his peregrinations through every plausible sequence of rooms and corridors. When things turned out badly from the simulator’s God’s-eye-view, she pored over the visual and auditory cues accessible to the drones in a selection of the failed cases, and refined her software to take account of what she’d missed.
By midnight she was exhausted, but she had the mission either succeeding completely or aborting undetected in 98.7% of the simulations. That would have to be good enough. The other targets were going to be more difficult; she needed to move on.
6
With every day that passed Natalie worked longer, but her short bouts of sleep came fast and ran deep, as if her brain had started concentrating some endogenous narcotic brew and would dispense the thick black distillate the moment she closed her eyes.
In the early hours of Monday morning, she dreamed that she was taking her final exam in machine vision. Sam was seated three rows behind her, throwing wads of chewing gum that stuck in her hair, but she knew that if she turned around to whisper an angry reprimand he’d only ignore it, and it wasn’t worth the risk of being accused of cheating.
She glanced up at the clock to check the time; just seconds remained, but she felt satisfied with her answers. But when she looked down at the exam paper she realized that she’d misread the questions and filled the booklet with useless non sequiturs.
She woke and marched to the shower to clear her head, trying to convince herself that she hadn’t merely dreamed all the progress she’d made. But the truth was, target C was almost done. The ordeal was nearly over.
It was still early, but Sam had grown used to her schedule. Natalie confined herself to jokes and small talk; the more matter-of-fact they kept the conversations, the easier it was on both of them. Until he was actually free, she couldn’t afford to let her emotions take over.
Target C had a husband and two school-age children, but if their domestic routine followed its usual pattern they would be out of the house well before the trigger – expected at eleven a.m. in C’s east-coast time zone. The most worrying thing about C was not her family, but the way she kept changing the decorative skins she’d bought for her wallet: the surveillance, going back twelve months, revealed no fewer than four different designs. Natalie could accept that anyone might have their personal esthetic whims, even when it came to this most utilitarian of items. But it was hard to believe that it had never once crossed target C’s mind that these unpredictable embellishments would make it so much harder for her to mistake another wallet for her own.
Still, the last surveillance imagery was only ten days old, and it showed a skin that was no different from that on the planted fake. The odds weren’t bad that it would remain in place, and the changes in style on the previous occasions had been so clear that the drones would have no difficulty noticing if the fake had gone out of fashion. Lewis’s people had not been foolhardy enough to try to wrap their substitute in some kind of infinitely reconfigurable chameleon device; visually, these ten-dollar skins were not unforgeable works of art, but they did come with different textures – slick, metallic, silky. Half-fooling a willing participant in a VR game with a haptic interface was one thing, but no hardware on the planet could morph from brushed steel to lamb’s fleece well enough to convince someone who’d held the real thing just seconds before.
Natalie started the simulations running. Target C had a strong aversion to insects, and every room was fitted with an eliminator, but even these low-powered pinprick lasers could not be unleashed in a human-occupied space without rigorous certification that ensur
ed their compliance with published standards. Insects followed characteristic, species-specific flight patterns, and the eliminators were required to give any ambiguous object the benefit of the doubt, lest some poor child flicking an apple seed off her plate or brushing glitter from her home-made fairy wand summon unfriendly fire from the ceiling. The drones didn’t need to imitate any particular, benign airborne debris; they merely had to exhibit an acceleration profile a few standard deviations away from anything seen in the official laboratory studies of Musca, Culex or Aedes. Unlike target B’s cat, the necessary strictures were completely predictable.
With the count of trials rising into seven digits and still no atonal squawk of failure, Natalie let herself relax a little and close her eyes. The midnight deadline was still fourteen hours away. She’d sent versions of her work for the other two targets to her “Team Leader” – as the collaboration software would have it – and received no complaints. Let these clowns run off to the Bahamas with their billions, and let the victims learn to use banks like normal people. She’d done the only honorable thing under the circumstances, and she had nothing to be ashamed of. Whatever the authorities decided, she could still look herself – and any juror – in the eye.
She opened her eyes. Why, exactly, did she believe that Lewis’s people would let her live to confess her crimes? Because she’d been a good girl and done as she was told?
Lewis had met her in a public place, making her feel safer about the encounter and seeming to offer a degree of insurance: if she vanished, or turned up dead, the authorities would scour the surveillance records and reconstruct her movements. A judge was much less likely to sign a warrant for the same trawling expedition if a living, breathing woman and her mildly mutilated brother went to the police with an attention-seeking story that positioned them in starring roles in the heist – and in any case, a shared meal proved nothing about her dinner companion.
But all of that presupposed that there really were records of the meeting: that the flock of benign surveillance drones that watched over downtown New Orleans had been as vigilant as ever that night – even in the places her adversaries had chosen to send her. Who was to say that they hadn’t infiltrated the flock: corrupted the software in existing drones, or found a way to substitute their own impostors?
If there was nothing at all to tie Lewis to her – save the microscopic chance that some diner in the food court that night would remember the two of them – why would the thieves leave any loose ends?
Natalie tried to keep her face locked in the same expression of exhaustion and grim resolve that she’d felt being etched into it over the last five days; the whole apartment was probably full of the same kind of micro-cameras that had documented the targets’ lives in such detail. And for all she knew there could be hidden drones too, far more dangerous than anything the targets were facing: robot wasps with fatal stings. A week ago that would have sounded like florid paranoia, but now it was the most reasonable thing she could imagine, and the only thoughts that seemed truly delusional were those of walking away from this unscathed.
She went to the kitchen and made fresh coffee, standing by the pot with her eyes half-closed. Apart from any cameras on the walls, her computer was sure to be infested with spyware. They would have done the same to the one in her office at UNO – and in any case, she doubted that her criminal overseers would be happy if she suddenly decided to show up at work.
When the coffee was ready she stirred in three spoonfuls of sugar; before the crisis she’d gone without, but now she’d been escalating the dose day by day in the hope of shoring up her flagging powers of concentration. She carried the mug back toward her desk, squinting wearily at the screen as she approached, hoping that she wasn’t over-playing her frazzled sleep-walker’s demeanor.
She tripped and staggered, spilling the sticky, scalding brew straight down the air vent at the top of her workstation. The fans within blew out a geyser of mud-colored liquid for a second or two, with specks reaching as high as the ceiling, then the whole machine shut down, plunging the room into silence.
Natalie spent half a minute swearing and sobbing, then she picked up her phone. She made five calls to local outlets that might – just conceivably – have supplied a replacement, but none of them had a suitably powerful model in stock, and the ones they could offer her would have slowed the simulations to a crawl. She pushed the last salesperson hard, for effect, but not even a premium delivery charge could summon what she needed by drone from the Atlanta warehouse in time.
Finally, as if in desperation, she gritted her teeth and availed herself of the only remaining solution.
“I’d like to rent a cubicle for twelve hours.”
“Any secretarial services?” the booking bot asked.
“No.”
“Any IT requirements?”
“You bet.” She reeled them off, but the bot was unfazed. The firm she’d chosen was accustomed to catering for architects and engineers, caught out with some processor-intensive emergency that was too commercially sensitive to be run in the cloud, or simply too awkward to refactor for a change of platform. It was the most logical place for her to go, given that the university was out of bounds – but it would have taken extraordinary prescience for Lewis’s gang to have pre-bugged the place.
Natalie caught a bus into the city. A fly with an odd bluish tint to its body crawled over the windowpane beside her; she watched it for a while, then reached out and squashed it with the side of her fist and inspected its soft remains.
At the office complex, the demands of security and climate control had her pass through half a dozen close-fitting doors. Between these welcome barriers she ran fingers through her hair, brushed her arms and legs, and flattened her back against the nearest wall. The security guards watching on closed circuit could think what they liked, so long as she didn’t look quite crazy enough to be thrown out.
On the eleventh floor, she entered the tiny cubicle assigned to her, closed the door and started loading the most recent hourly backup of her project from the flash drive she’d brought. This version wasn’t quite the one that had been doing so well in the simulations, but she remembered exactly what changes she’d need to make to bring it up to that level.
The gang’s roboticists would run tests of their own, but if she held off delivering the software until just before midnight they would be under enormous pressure. In a finite time there was only so much checking her fellow humans could do, and not a lot of point in them trying to wade manually through every line of code and every neural-net template included in the package. Like her, in the end they would be forced to put their trust in the simulations.
As instructed, Natalie had programmed her drones to wake and commence their mission, not at any pre-determined time, but on receipt of an external infrasound cue. It made sense to allow that much flexibility, in case the lurch in the markets that was meant to prompt people to reach for their wallets came later than expected.
One side effect of this decision was that for targets whose schedules were different for every day of the week, simulations had to be run separately for each day. But where there was no difference except for weekdays versus weekends, the simulated drones were fed no finer distinction, and the millions of permutations to be tested could play out much faster by limiting them to this simple dichotomy.
Target C stuck to a single routine from Monday to Friday, so as far as the simulations for her were concerned, they were taking place only on a generic weekday. Anything in the software that relied on it being a specific day of the week wouldn’t come into play, in the simulations.
In the real world, though, Thursday would still announce itself as Thursday in the drones’ internal clocks. And that very fact would be enough to tell the drones’ software that they were out of VR and moving through the land of flesh and blood.
Natalie couldn’t be sure that D-day would arrive on schedule, but she had no choice but to trust the swindlers to accomplish their first, enablin
g feat exactly as they’d planned it all along.
7
“This should be our last call,” Natalie told Sam.
“There are two ways I could take that,” he joked.
“Take it the good way.”
“So they’re happy with your work?” Sam tried to make that sound like a joke, too, but he couldn’t quite pull it off.
“I’ve had no complaints.”
“I always knew you’d end up as a mob accountant.”
“Ha!” She’d had a summer job once that included book-keeping for a small construction firm with a shady reputation, but every transaction that had crossed her desk had appeared entirely legitimate.
“Stay strong,” she said. “I’ll see you soon.”
Sam just nodded and lowered his eyes. She cut the link.
Natalie waited five more minutes, for six o’clock sharp. If the market trigger was coming, Lewis’s people would have recognized the early signs of its onset hours ago, but she’d had no idea what to look for, and she hadn’t wanted to attract suspicion by trawling the financial news. It would be impossible to load an entirely new copy of the drones’ software via infrasound in less than two days – but in less than an hour, an experienced team might be able to write and deliver a small patch that neutralized the effects of her sabotage.
There would be no moment of perfect safety. Natalie used the collaboration software to send a message: Flaw in the code for target C. Need to discuss urgently.
Twenty seconds later, her phone rang.
“What are you talking about?” Lewis demanded angrily.
“It hasn’t started executing yet, has it?” Natalie did her best to sound businesslike: she was acknowledging her screw-up, but she was still the voice of authority when it came to these drones, and she was asking for the state of play in order to salvage the situation as rapidly as possible.
