“We have to face the fact that at some point in the next few weeks this whole situation is going to go critical. The remaining Agents are going to find out what we are doing and … well … we have to assume that they are going to launch their virus … at the very least. They may not be able to kill us all, but once they know that we are becoming immune, we have to assume that the AIs will react by either attacking immediately, hoping the immunity is not too widespread, or attempting to circumvent our antigen and build a new virus. John has said that if they get hold of a sample of the antigen they could, hypothetically, develop a pathogen that can withstand the antigen’s defenses. And if we delay our attack on the satellites long enough for that to happen … we will be done. End of game.”

They sat silent. Ayala and Jack Toranssen instinctively looked at the colonel, but he was as stunned as they were.

After a moment it was Martin, somewhat hesitantly, who offered up a thought, “So what you are saying is: we have up until the moment that the AIs figure out what is happening. Once that happens we have to launch our attack, whether the antigen is fully dispersed or not, we have to launch. If they can potentially counter the antigen we cannot give them the opportunity to do so. We will have to save whoever is already immunized.”

At Neal’s nod, Martin then asked, “I am assuming we cannot further speed the spread of the cure?”

“That is statistically impossible.” said Ayala, shaking her head, “I personally injected over three hundred people with the vaccine. That was an average of ten ‘covert’ injections a day. I also enlisted several friends and ex-colleagues to distribute a further 250 of the doses, including the colonel.”

“But it has been months since that effort. It is out there. Each week it is spreading to millions of people. If we have less than a month left to the reach 100% dispersion in Europe, that means that ten percent of the population is already immunized. That’s one hundred million people in Europe alone. To noticeably speed the process up now we would need to manually immunize millions … and there is simply no way to do that, not without alerting the Agents to their actions. It is simply impossible.”

There had always been a diminishing marginal return from further injections, which they had matched against a serious and steadily increasing risk of discovery every time one of the team or its proxies stabbed another stranger with the drug.

A sad resignation settled over the room. People who had worked round the clock for months under the constant threat of discovery were now somewhat inured to it all, and faced with facts like these they knew they had to simply accept the potential for mass casualties, just as they had accepted the potential for their own. And so no one expected the next question.