Thank you for the quick and helpful reply, and for the welcome.

"and security (not noted in government establishments)" LOL

Yes, they are civil servants based in Washington. Essentially the story is about trying to find out if an ex-general (now a civil servant) can be trusted in the investigation of a corrupt army officer in Afghanistan, or whether he is actually involved. Because the other civil servant can't trust the CIA etc. in the circumstances (out-ranked) he is using a less-than-legal bunch of people to help him out. These are world-class criminals with a lot of resources to hand.

Is that enough background? I just need to be able to sketch out him asking for help and the bunch of criminals (he's worked with them before) delivering the solution.