“Assume you’re right, and Bowman’s going to set off an RDD at the party,” said Andrea. “How? Like I said, we have officers co-ordinating with police, and they’re already on alert because of the PM’s visit. How’s he going to get in the venue?”
“Who says he has to be anywhere near it?” Bridge turned to the GCHQ video feed, where Steve Wicker had quietly slid into view beside Patel. “He’s been buying up drones for testing, and now he has the means to control them at a distance. Right, Steve?”
He nodded. “Afraid so. If he’s been working on signal range extenders and custom transceivers, he could be half a kilometre from the place, maybe more. And without knowing where he’s likely to be, isolating and tracing his signal will be tricky. A dirtbox would grab every signal around, but how would we know which one was him?”
“Hang on, before we get too technical,” Giles interrupted, and checked his watch. “Can’t we just cancel the party, or move the venue? It doesn’t start for thirty minutes.”
“I don’t think that’s a good idea,” said Bridge. “This is our chance to draw Bowman out. If we evacuate, he’ll know we’re onto him and vanish back into the shadows, complete with his radioactive material and drone collection.”
Giles nodded. “Replacing an attack we’re expecting with a future one that’s completely unknown to us.”
“He may not wait long,” said Henri over the phone. “The smugglers both succumbed to radiation poisoning, and they only had the material for three weeks, tops.”
“Bowman’s surely better prepared to handle it,” said Bridge, “but point taken. And it reinforces our theory. He timed the material’s arrival so he wouldn’t have to store it for long before using it.”
“I was going to suggest a sniper team around the building to shoot the drone down,” said Andrea, “but if the drone itself is carrying a bomb…”
Ciaran said, “Steve’s right, locating the signal will be tricky. But if we can, then we could swamp the source. No signal; no flying instructions. Most drones will default to hovering in place, or safely descend to earth, when there’s no signal or a low battery.”
“Perhaps I should have emphasised the difficulty more,” said Steve. “If he’s using multiple extenders and transceivers, combined with the hundreds of active wifi signals at any given location in London, this is like half a needle in ten haystacks. We’d have to get down there, figure out which local signal might be Bowman, then hack and piggyback it to trace to source, and finally hope we’d picked the right one to start with. And on top of all that, we have to assume he’s built redundancy into the system.”
“We also couldn’t begin isolating until the drone was in range, because we have no idea where Bowman himself is,” added Ciaran. “It’s not enough time.”
“So just cut them all off,” said Monica. “Use a jambox to shut down everything around the venue.”
Bridge shook her head. “Too many legit signals that might get shut down. Guy’s Hospital, London Bridge station, God knows how many internal signals to keep the Shard itself operating. Jamboxes are chainsaws, when what we need is a scalpel to attack only the drone signal…” She stopped herself, an idea forming.
Giles saw the change and raised an eyebrow. “I can almost hear gears turning. Bridge?”
“Ciaran’s right, we don’t know where Bowman is. But we do know where the drone will be, and that means we can lay a trap, so long as I can get to the venue in time. As soon as the drone comes within range, boom.”
“I’m on my way there as soon as I get off this call,” said Andrea. “I can swing by and pick you up. But what kind of trap do you mean? Something to catch a drone?”
“Something like that. It’s called MaXrIoT.”
81
At any other time, Bridge would have enjoyed watching Andrea’s driver break enough traffic laws to get his licence revoked every hundred metres. Instead she was focused on her HP laptop, running a custom signal scanner and packet sniffing software. As Steve had said, the streets of London were saturated with hundreds of wifi signals and gigabytes of online traffic at every moment. Bridge knew the signal she was looking for wouldn’t be in range yet, as they raced toward the Shard, but it was better to get the software up and running early. Andrea was in the front passenger seat, Giles in the back with Bridge. Both were talking non-stop into their phones, taking reports and issuing clipped instructions.
“Three minutes,” said the driver as he ran a red traffic light and leaned hard on the wheel, to weave between the opposite lane of traffic and an illegally-parked white van. Bridge held the HP tight as she and Giles slid across the back seat.
Andrea turned to them and said, “No sign of anything airborne at the venue, according to our people. Even in the dark, you’d expect them to see something out of the window, right?”
“Maybe, but only if it was on a similar plane,” said Bridge. “If he flies really high, or really low, they wouldn’t see it. And then he could quickly drop or ascend to the venue floor, and they’d only have seconds to spot it. What you really need is something like proximity sensors on the outside of the building to warn against this sort of thing.”
“I somehow doubt they had things like this in mind when they designed the place. It’s all a bit sci-fi.”
“iPhones were sci-fi until suddenly they weren’t,” said Bridge. “In the meantime, we’ve just got to cope. Tell them to keep looking, while I keep scanning.” Andrea returned to her phone, shouting instructions.
“One minute,” said the driver, squeezing between taxicabs bound for London Bridge station. The car’s passenger side wing scraped lightly against one of the taxis, and Bridge wondered if the cabbie would be able to get compensation from MI5. How would
