The Abomination (33 page)

“I have a murder involving Croatia, Camp Ederle, the Church, a mental hospital, an MCI employee, the Mafia. . .” Kat got up and listed the connections. Point for point, the two lists were almost identical. “Daniele, your turn.”

He waved away the marker. “The only concrete thing I have is MCI.”

Kat wrote it down for him. “Then that's the start point. We have to follow the links between MCI and these other players.” She hesitated. “Daniele, that means I'm letting you try Barbara Holton's hard drive. Amongst other things, I need to know if you can reconstruct her emails to and from Bob Findlater.”

He nodded. “I can get on with that while the two of you look for overlaps elsewhere.”

“No,” Kat said, shaking her head.

“Why not?”

“While you're working on that hard drive, either Holly or I will watch you at all times.” She held up a hand to forestall his objections. “I know, I know – I'm sure if you wanted to you could lift the information from it without my even noticing. The point is, I'm crossing a line just by letting you touch it. I need to limit my culpability from ‘insanely trusting' to ‘criminally negligent'. Which brings me to my second point. You're still refusing, as far as I can see, to actually delve inside Carnivia and tell us what's going on there. So I'm going to ask you one more time, with no judges or lawyers present: is there anything that you can do to trace that information that you haven't already done?”

He met her gaze calmly. “There is one thing.”

“Go on.”

“When I followed one of the women priests on Carnivia, I came across a chest with a
stećak
marking on it, similar in design to the ones you found at Poveglia. I realised that the chest was a repository – a way of transferring large amounts of data between individuals.”

“And?” Kat said.

“I discovered that several repositories in Carnivia were customised with the same symbol. They were clearly being used to transfer files relating to a specific project. It seems a reasonable hypothesis that it might be something to do with your murders, since in at least one case whoever was expecting the information never received it.”

“Who was the recipient?”

“I don't know. I need the algorithm – the encryption key – that Barbara Holton used to log on with, which would have been automatically saved to her hard drive along with her other personal information. If I can retrieve that, I'll know who she was really working for. But I'm willing to bet it wasn't Bob Findlater.”

KEEPING AN EYE
on Daniele while he worked on the hard drive turned out to be rather more complicated than Kat had anticipated. Naively, she'd imagined he'd simply hook the drive up to a computer and run some tests on it. In fact, it turned out, the first thing he needed was a clean room in which to work.

And a “clean room”, it transpired, didn't mean going over Ca' Barbo with a Hoover.

“In order to restore the drive, I need to take it apart and physically clean the seawater residue off the platters,” he explained, sighing at their ignorance. “Computer hard drives are sealed units for a very good reason. Ordinary air contains microscopic dust particles that would scour them like sandpaper. I need a closed environment, with a filtered recirculating airflow.”

Using materials from a hardware store, Daniele set about constructing a sealed booth with its own air-conditioning unit, lined with carbon-fibre material to reduce the possibility of static. He turned out to be a methodical, painstaking craftsman, never cutting corners and making sure each stage was perfect before going onto the next.

When it was built, the booth was given a separate power supply, to minimise electrical surges, and an ioniser to dissipate any charges that built up. Special plastic-coated tools were cleaned and demagnetised before being installed on the carbon-fibre-lined workbench. Only then did he put on a forensic suit and enter the booth with the drive.

The booth had to be sealed while he was working, but he'd reluctantly agreed to a video link so that the two professionals could observe him. In practice, however, Kat soon became impatient with the slow pace of the work, and left Holly to supervise Daniele while she went off to continue showing Bob Findlater's picture to the prostitutes around Santa Lucia.

“So how come the Carabinieri's IT guy didn't do any of this?” Holly asked over the link as Daniele began dismantling the hard drive. Evidently it wasn't a completely stupid question: instead of snarling, he actually honoured her with an answer.

“Most computer experts are actually just experts in which specialist software to use,” he said. “To inspect a hard drive, for example, you'd rig it up to a program like Helix or IXimager. That tells you what's in the slack space – the bits of data that have been deleted but not actually wiped from the machine. For ninety per cent of investigations, that's perfectly sufficient.”

He broke off to place the hard drive covers to one side. “For more advanced stuff, like the Madrid bombing or the Shuttle disaster, almost every government agency in the world uses an outfit called Kroll Ontrack. In fact, if I had a fire-damaged hard drive in one of my own computers, that's probably who I'd go to as well. Seawater's a bit more specialist, though. The problem isn't so much the water itself – the actual data is stored magnetically – as what it leaves behind when it dries. When someone like Malli starts the drive up to copy it, the residue on the spinning disc scours into the surface, corrupting the data. I'm hoping that Malli didn't try too hard, in fact, because the less he did, the better my chances are.”

He donned a surgical mask, powder-free latex gloves and a static-dispersing wrist-strap as he began the delicate operation of freeing the platters.

“We're in luck,” his muffled voice said over the feed. “There's still moisture in here.”

“That's good?”

“It's like the wooden pilings that hold up these Venetian houses. So long as they stay wet, they don't corrode.”

He placed the platters in a bowl of purified water. “There. Now I need to leave them to soak.”

He exited the booth and stripped off the mask and forensic suit. She saw his eyes go to the whiteboards covered with mathematical notations at the back of the room.

“What are those?” she asked curiously.

He grunted. “A maths problem.”

“I gathered that. Is it something to do with computing?”

“In a manner of speaking.” He glanced at her. “I doubt you'll understand.”

“So do I, but tell me anyway.”

He picked up a marker and went over to the board, tracing a path through the formulae. “The problem is called
P versus NP
. Effectively, it boils down to a simple question: if a computer can be programmed to verify the answer to a theorem, why can't it be programmed to solve the theorem in the first place? It's one of the seven Millennium Prize problems in mathematics. Only one has been solved so far.”

“And you think you can solve it?”

“I used to think so. But now I doubt that anyone can.”

“So why keep trying?”

“Why?” he echoed, surprised. “Because it's beautiful. Like a piece of music, or a sculpture. The problem itself, I mean – it says more about the condition of being human than any symphony or portrait ever could.”

“You mean you just like to look at it?”

“Look at it, listen to it . . . these aren't adequate words. Here. . .” He crossed to where another whiteboard stood by a wall and slid it to one side. Behind it was an abstract painting. “That's a De Chirico. My father thought it one of the most sublime things in his collection. And here. . .” He slid the whiteboard back so that it covered the painting again. On it was the notation
e
^iΠ
+ 1 = 0.

“That's Euler's Identity. Any serious mathematician will tell you that it's one of the most profound works of art ever created – more beautiful than the Sistine Chapel, more elegant than the Parthenon, purer than the Requiem Mass. In just three simple steps it answers one of the most fundamental questions of existence.”

“Which is . . .?”

“Oh – ‘Why are circles round?'”

While Holly was still mentally scratching her head about that one, Daniele led her to the next room. In the corner was an elongated sculpture that looked to her like a Giacometti. Incongruously, it had been given Ray-Bans and a trapper's hat to wear. But it was the fresco on the wall, a landscape, to which he was pointing. Over it he'd stuck a Post-it on which he'd written the numbers 6, 28 and 496.

“Those are what's called ‘perfect numbers'. That means if you take all the numbers they can be divided by, and add them together, you get the same number you started with. So the number 6, for example, can be divided by 1, 2 and 3. Add 1, 2 and 3 together, and you also get 6. The Ancient Greeks thought the perfect number pattern was proof of the inherent harmony of nature.”

“So the fresco is a painting of a landscape,” she said slowly, “and the other is the . . . the. . .” She struggled to find the right word.

“The essence of the landscape,” he finished for her. “Exactly.”

She began to understand now. What had appeared to be a casual defacing of the palace's artworks – his father's hated legacy – now looked like a reinterpretation of them. Several times after that she pointed to a Post-it stuck on a priceless work of art and asked him what it meant. A seascape bore the notation
X
_o
(N)
. “The modularity theorem,” he explained. And a still life of flowers and fruits was plastered with what he told her were Mandelbrot equations. The actual mathematics might be far too advanced for her, but she knew enough to comprehend that Daniele Barbo had a mind unlike that of any other person she had ever met.

At last Daniele returned to the booth, removed the hard drive platters from the bowl in which they had been soaking, and opened a crate of aerosols.

“Those are air dusters, presumably?” Holly said.

“Pretty much. Canned air isn't actually air – it's a cocktail of gases like trifluoroethane that compress easily. The problem is that to stop kids from sniffing it, manufacturers add another chemical to make it bitter, and the bittering agent can leave a residue. This is NASA-grade canned air.”

It was as he was painstakingly drying off the platters that she was struck by a thought.

“Daniele, I think I've worked out why you built Carnivia.”

He didn't reply, but over the video link she saw him stiffen.

Too late, she realised she was blundering into a minefield.
Oh well: there's no backing out now
.

“Everyone calls it a social networking site,” she said. “And I've been puzzled by that, because it seems like a contradiction – you're the least social person I've ever met. But I've been thinking about those maths problems of yours. You see the world as a series of equations, don't you? Yet the truth is that the world isn't quite like that – it's untidy, and unpredictable, and various random factors keep messing up the picture.”

“Which leads you to what conclusion, Second Lieutenant?” he said softly.

“I think the real world turned out to be too random a place in which to try to solve puzzles like
P versus NP
, or whatever you called it. So you built your own, neater version instead, one where you could limit the variables. All those people who join Carnivia . . . unwittingly, they're all just part of a giant mathematics simulation. Like a glass-sided ants' nest in a laboratory. And that's why you care about Carnivia so much, isn't it? Not because of the four million users, or however many it is. It's because the puzzle you built it to process isn't solved yet.”

“Hmm,” he said non-committally. There was a long silence, followed only by the hiss of air as he applied another air duster to the hard drive.

In the circumstances, she thought, that was as good an answer as she was likely to get.

When the hard drive was finally dry, Daniele emerged from his booth with a black box the size of a cigarette packet in his hand

“It's fixed,” he said simply. “Or at least, enough to give it a try.”

He hooked the hard drive up to a computer, plugging it into a USB port just as if it were a memory stick.

“I'm not going to try to run it with Windows,” he said, “just in case it's programmed to erase itself. And this way I don't need to know Barbara Holton's username or password.”

“How do you know what you're looking for?”

“I don't. But Carnivia saves user information to a very specific location. I'll start there and work backwards.”

THEY GATHERED AT
the Foundation's latest art exhibition. Four men, all in their sixties, none of whom had any interest in art. Each positioned himself in front of a different picture. Should a tourist turn up – an unlikely occurrence, since the pictures in this room had been carefully selected from the most unfashionable, unappealing items in the late Matteo Barbo's collection – the receptionist would turn them away, explaining that as it was almost lunchtime no more visitors were being admitted. The tourist would shrug, and reflect that this kind of thing happened all the time in Italy.

“I'm not sure it was wise to send Findlater himself,” Ian Gilroy said reflectively to the picture in front of him.

“We had forty-eight hours' notice. There was no one else who understood the gravity of the situation,” a voice responded to his right.

Gilroy turned, and walked across the room to where Balla's
The Car Has Passed
hung against a plain red background.

“My understanding is that the Carabinieri investigation is now closed,” the third man said. “The prosecutor has informed me that the final report will be circulated within days.”