Ryan Drake is an agent with the CIA.
Drake is also British which makes him quite a rarity in the Agency and sometimes the subject of suspicion if not actual hostility. The UK might be the US's closest ally but it was not the US so why was a British citizen employed by one of America's most secretive organization - that was a question asked on more than one occasion.
His unusual situation in the CIA was not made any better by his role with the Company. Drake was a leader with a Special Investigation Team, a "small but prolific sub-unit of Special Activities Division formed to investigate, track down, and, if possible, bring home missing CIA operatives." On the one hand, if you went missing through no fault of your own, chances were that Drake's team or one like it would try to rescue you. That was a good thing. The other hand said, though, that if you left on your own but without permission, they would hunt you down, a not-so-good thing.
They were called the Shepherds and there were six team leaders of them. Each leader could pull his or her people from pool of agents but by and large the teams were set through experience and confidence. Drake had his list of those he trusted and those he didn't.
Drake came to the CIA through his involvement in Afghanistan. Now in his late 30's, Drake had joined the British military in the mid 90's. He was a part of the Parachute Regiment for a couple of years before being accepted in the prestigious SAS. With them he did two tours of combat including a highly classified Operation Hydra.
He had earned two commendations for his bravery. He then did something he still does not like thinking about, let alone talking of. A court martial ensued followed by a dishonorable dischage. Then came the unusual offer of a job with the CIA and, desperately needing something to grab onto, he took it.
As the series begins, Drake has been in his job of Shepherd leader for four years. He is very good at it but the dark cloud still hangs over him, at least in his mind.