As I sat in the unnatural silence of our tech lab I had to grudgingly concede that A1 had done the right thing in not telling me about the nano mic earlier, and also that it was right to use this to our advantage.
As quietly as possible Steve put the thin silver chain with the small plastic box containing the bug around my neck. They had encased it in a model of my Firewire port and padded it to mimic the acoustics of where it had come from. It was gaffa taped to my neck so as not to be visible beneath a shirt collar, not that anyone would be looking for it.
"Okay," said Steve, going into the prearranged script. "You can relax now, that's all the tests over, Agent 4."
"Any problems?" I asked.
"No, there's still no trace of the virus or anything untoward."
"So you've still no idea how they got me on that bloody plane?" I added the bloody for good measure and injected some venom into the question that wasn't anything to do with acting.
"Sorry, we're still stumped."
I sighed loudly.
"Okay, thanks, Steve."
I went back to my office and made the call.
"I'm leaving now, sir, starting my long weekend."
"Oh yes," said A1, "going anywhere nice?"
"Driving out to the country to meet Barbara, she's been staying with relatives."
"Well, have a nice time, see you Monday."
"Bye."
I walked down to the underground car park and got into the van, switching the radio on loudly to cover any sounds from the people in the back. I adjusted the modified sat nav. It was inconvenient to have to keep looking at it but we couldn't risk any directions being given by headset. The reverse engineering that had been done on the bug required me to carry it with me in order for us to find the receiver.
All they'd been able to manage in such a short space of time was was a system which would tell me whether I was getting further away from or closer to the signal. Someone in the back would keep a track of this information and feed directions through to my sat nav. It was clunky but it should yield results eventually and hopefully become more accurate the closer we got.
I turned left on a whim and drove in a straight line.
After a few minutes the screen flashed at me to turn right.
This tedious procedure continued for about two hours.
The sat nav flashed the words 'pull over' and a longer message began to appear.
It took a few minutes to find a parking space, after which I scrolled back to the start of the message. It said that they had now isolated the signal and the receiver was within a two mile radius of a spot indicated on the map. I typed a reply and pulled back out into the traffic.
Another two hours of tedious twists and turns eventually pinpointed an area small enough to search with our own detectors. I drove to the centre of the area and switched the engine off, leaving the radio on. I carefully removed the necklace and bug and placed it on the dashboard near a speaker. As quietly as possible I slipped out of the van and closed the door.
In the back of the van they were thankfully making much swifter progress.
After a few minutes we'd isolated the building where the receiver was. A search of the electoral register told us that it was a top floor flat. It was too small to contain many occupants so three of us felt confident enough to go in with just handguns.
22, 45 and I knocked on the door but nobody answered. 22 was the lock-picking expert among us and it took him no more than a few seconds to open the simple yale lock on this rundown, converted house.
There were no signs of life as we ascended the stairs.
My hand held scanner told me there was nobody in the attic flat so 22 again picked the lock. Careful to look out for booby traps, we entered straight into a small living room. On a coffee table in the corner was a laptop and large aerial. The laptop was on and a message was flashing on the screen.
"Someone left it recording and they've run out of hard drive space," said 22.
He rooted around the few objects on the desk.
"There's a large external hard drive so it... hang on a minute."
He sat down at the laptop while 45 and I searched the rest of the flat for any useful forensic evidence. The thin layers of dust and total lack of any food or toiletries suggested it hadn't been inhabited for some time.
"This has been left for several weeks," said 22 as we returned to the living room.
"I don't think anyone's lived here during that time," I said, "there's not so much as a tea bag or a roll of toilet paper."
"It's run out of space to save any further recordings, but it may still be transmitting, that is passing the signal to somewhere else."
He turned up the volume on the laptop and we heard the sound of the vans radio.
"Hmm," pondered 22, "this could take some figuring out. Even though it's not recording anything it is still receiving the signal. I could switch off the laptop and unplug the aerial but if anyone is listening elsewhere that would alert them to it's discovery."
He took out his phone.
"Steve, can you come up here, please?"
"I'll go and let him in," said 45.
"Why record it if there's nobody here to check on it?" I asked.
"Obviously they intended at some point to come back and retrieve the equipment. We know for a fact that information you gave was passed on but if we caught or killed everyone at Cambridge then this is just sitting here by itself. It shouldn't take long for Steve to see if this is passing the signal to another location. If it isn't then we can safely assume that we've got the whole group."
Steve did indeed confirm after half an hour that no signal was being sent so we dismantled the equipment and called the forensic team in to sweep the flat. Matching this location to one of the group would be very helpful.