They were close enough for the sniffer software to pick up every signal around the building, and Bridge filtered them out as quickly as she could. Ciaran, Monica, and Steve Wicker were in a secure VOIP chatroom connected to a Jawbone bluetooth mic wrapped around her ear, but up till now all she’d heard from it was the sound of keyboards clacking. She pressed Talk on the headset and said, “Shitloads of signals, as expected, but I’m not seeing anything that looks likely. None of the transit delay patterns look like obvious remote control packets.”
“Maybe the drone isn’t there yet,” said Ciaran. “The party’s scheduled to last ninety minutes, you could be in for a long wait.”
“Sudden thought,” said Steve, “Bridge, how granular is your frequency selector? Is it default?”
“No, replacement upgrade,” she replied. “Point-oh-one gigahertz increments. What are you thinking?”
“If he’s building his own extenders, he might have them fixed on a non-regular frequency. For this usage, we’d normally assume low frequency would be best, right? Drone control is low data bandwidth, and low frequency is more reliable over distance.”
“Here,” said the driver as they stopped in front of the Shard, and the three passenger doors automatically popped open. Andrea and Giles de-bussed with practised efficiency, and Andrea immediately shouted at the police to turn off their flashing lights. Bridge, meanwhile, struggled to climb out without accidentally closing her laptop, and found herself surrounded by police officers and vehicles on the narrow road. The MI5 driver showed no sign of going anywhere, so she used his car roof as a makeshift desk for the HP and began adjusting the scanner software’s frequency.
“All right, let’s see if he’s broadcasting on an unusually high frequency. Kind of crappy over long distance, but if he’s packed the area with custom transceivers, there could be one right next door.”
“It’s what I’d do,” said Steve. “Not sure what that says about me, but —”
“What it says is you’re a bloody genius,” said Bridge as the software lit up. “I reckon I’ve found him. There’s an ultra-high frequency signal, just idling in this area.”
“What do you mean, idling?” asked Giles.
“I mean it’s just sitting there, like in a standby mode. All it’s doing is broadcasting itself as ready, tiny packets, but nothing’s actually happening.”
“Definitely sounds like our guy,” said Ciaran. “And if it’s idle, that means the drone isn’t in range yet.”
“If we’re right about the plan, and if this is the right signal,” said Bridge. “Lot of ifs.” Nobody replied. They were all thinking the same thing, but were too polite to say it out loud. What if Bridge’s theory is a load of rubbish?
“I’ve started a traceroute,” said Steve. “You never know, we might get lucky.”
Giles had been watching in silence over Bridge’s shoulder, letting her work, while Andrea talked to the police officers surrounding the building. Now she returned, wearing a radio earpiece, and stood on her tiptoes to peer at the laptop screen. “Did I hear that right? You’ve found it?”
“We think so,” said Giles. “Won’t know for certain until he attacks.”
“Oh, that’s very comforting. I do love standing around, waiting for something to happen.”
“If I’m right, we won’t have too long to wait,” said Bridge.
“If you’re right,” repeated Andrea, with emphasis. “We had a word for people like you in the Forces; Quasis.”
Bridge tried to figure out what the nickname could mean. “Quasi-skilled? Quasi-normal?” She shrugged in defeat.
Andrea smirked. “Quasimodo, you big daft. ’Cos you’ve always got a hunch.”
“Bit harsh,” Giles snorted.
“I didn’t know you were a soldier,” said Bridge, looking down at Andrea. “I thought…well, I mean…”
Andrea gave her a withering look. “No height requirement in the army, Ms Sharp. So long as I can kill you with one hand, it’s all good.”
Bridge looked to Giles for help. “Can’t tell if she’s joking.”
“Best tread carefully, just in case,” Giles said with a smile. “And be fair, Andrea. This isn’t some vague gut feeling. You saw the CTA’s evidence, and you know what Bridge found in Agenbeux.”
“Hang on, she’s read my reports?”
Giles shrugged. “More like an oral summary.”
Text scrolled up the side of a window on the laptop screen. “Activity,” said Bridge. “Here we go. Ultra-high frequency, RC-style packets. Hang on, though…there’s a side stream of really high-bandwidth, low-latency traffic, funnelled from multiple destinations. It’s like he’s watching Netflix on half a dozen monitors at once, or — shit, it’s multiple units. He’s not flying one drone, he’s got a bloody fleet of them.”
“The high traffic streams are probably mounted camera feeds,” said Monica through the headset. “Which suggests they’re being controlled directly, not following a pre-programmed route. That’s probably good for us.”
“Multiple drones?” said Andrea. “So which one has the material?”
Bridge frowned. “No idea. Maybe all of them.”
“Fucking hell. Right, I’m going in.” Andrea marched toward the entrance, shouting into her earpiece. “Move everyone away from the windows. Fast as you can, but be subtle. They may have cameras watching.” Bridge wasn’t sure how an entire party retreating could be in any way subtle, but that was Andrea’s problem. The Scot pointed at a police sergeant as she passed, and shouted, “You, get that woman with the laptop whatever she needs and stay with her till I say otherwise.” Then she ran into the building.
The sergeant jogged over. “What can I get for you, ma’am?”
“You can stop calling me ma’am for a start. It’s Bridge.” She turned to Giles. “We should probably get the fire service down here. And I guess a hazmat team might not be a bad idea, just in case.”
“Biohazard and CBRN fire already en route,” said Giles, “I called them from the car. Are you OK for power, connectivity, all that?”
“Yes, fine.” She turned back to the sergeant. “I don’t suppose I could get a cup of tea from somewhere?”
The policeman chuckled. “Absolutely, ma’am. You too, sir?”
“I should bloody coco,” said Giles. “Bridge, what are our chances? Is this hacking app of yours going to work?”
“All I can say is, it’s our best chance.
