Adrian Hell is an assassin.
He is mostly freelance for a good deal of the time we know him but he did get his training courtesy of some quality time spent in the service of the U.S. military. Then more training and more service and more experience with the CIA. Then a serious falling out (for very good reasons) and then the new career spent removing people other people want removed.
"Adrian Hell is an assassin. His name commands fear and respect in equal measure throughout the criminal underworld. But the former soldier is not without his demons. Desperate to forget a tragic past, he loses himself in the one thing he was good at: killing bad people he believes deserve a bullet."
When we first meet him he has been a paid assassin for some time. "I'm an assassin-a damn good one. Probably one of the best operating in North America today. I say that with no ego, it's just a fact. I've honed my craft over the last eleven years or so, ever since I left the CIA. Before that, I was military-first one through the door during Desert Shield. But since retiring, I found it hard to hold down a job that didn't involve shooting people. Old habits, I guess. So I've worked hard and done a few... questionable things over the years, but with some help, I've become a legend in the criminal fraternity as the only person worth hiring when you want a job done right."
He is choosey about his targets, though. "I won't ever pull the trigger unless I have proof the person deserves a bullet. And in my line of work, you deal with a lot of people who do terrible things, so I don't feel bad saying someone deserves to die."
How Adrian Hell got to be the kind of freelancer than he is we find told in a prequel adventure that takes us from an 18-year-old Army recruit from Nebraska named Adrian Hughes. It shows his training, going through Basic Training with a bit of an attitude which earns him the chance to do a whole lot more push-ups than he would have liked. [His attitude towards, well, everything, would not change much over the years but his understanding when to keep his thoughts to himself will improve - a tad.]
We are given glimpses into his service in the military to his being selected to work for the Agency and his first assignments for them. We can watch as he hones his impressive skills taking out enemies of the country all over the world. And we learn why, when he was considered to be one of the very best in the CIA, he abruptly stopped being in the CIA.