I would recommend.. care with this concept because I ran a similar idea a few months back (players are a cell assembled to reinforce Firewall in Lunar orbit following a breach of their security) and one of the players just became super-paranoid and simply REFUSED to do anything because 'it might be a trap'. I mean, refusing to even receive mission briefings in case the file contained a virus etc. Obviously dude has his own problems, but I think the mistake on my part was introducing the possibility of double agents and so on too early. It meant that the early sessions were a real struggle against the paranoids who literally didn't want to do anything that might pose a risk.
What I would recommend is starting off a bit vanilla - you are Firewall, go place, stop threat, hurray good job - and introduce the idea of a possible mole in the second session or even later. The realization that you might have already been given bad info is unsettling, but you have to keep going to find out what's going on, whereas the Player Logic if you START OFF with "someone might give you bad info" is often to distrust EVERYTHING and not do ANYTHING.
Which is a shame, because I was actually kind of pleased with how the double agent thing I'd written out had ended up even though the game petered out before they could unravel who it was; using the ideas of forking/merging and psychosurgery, I realized the best double agents are those who don't KNOW they're double agents and had a Firewall agent who was two modified beta forks. Individually, neither fork was aware of their own betrayal and thought they were doing internal security for Firewall.
