Gus Deacon is a freelance operative.
He wasn't for quite a while. Too long, if you ask him. He worked for the CIA under non-official cover for a good number of years, most of it working for a not very pleasant man named Clovis. Then something unpleasant happened, the mission he was on at the time went south quickly, and suddenly Deacon was not only persona-non-grata with the Agency, it was said by many there was a terminate-at-will put out on him.
So Deacon, a man used to action and danger, was out of a job and really just trying to stay alive. His graying hair and the lines around his eyes showed he was not the young man he once was and while his constantly looking eyes did not yet hold the appearance of a haunted man, they definitely reflected a hunted one.
And then an old colleague and sometimes friend came to call with an offer. Help someone that Clovis wanted helped and his status would change. He might not be welcomed back into the fold by the Agency but his "transgressions" would be forgiven.
Deacon did not feel he had transgressed in any way and the trouble that happened had not been of his making but he was wise enough to know what he knew and felt made no difference at all. The one-time-only offer was a way to a new life and he took it.
Working with Deacon is his good friend, Charlie Fischer, a former federal police office in West Germany before reunificiation and then with the GSG-9 counter-terrorism unit. Back in his day, it was vital to get the job done and sometimes questions were best not asked. As the 80s and 90s slipped away, though, new administrations had new ideas of what was acceptable and what was not and Fischer found himself not so wanted. Except by Deacon who knew that hard problems required hard men.
Together, they show they are hard men.