Kurt Harm is an agent with the CIA.
More specifically, he is an assassin, as denoted by an entertaining tag line for the first recorded adventure which reads, "Cleaning up the World. One Target at a Time." In a blurb about the first recorded adventure we are told that "Kurt Harm was a gifted assassin. He traveled the world as little more than a ghost, carrying out covert operations for his Special Forces unit. Then, one mission went horribly wrong. Harm thought he could put his sniper rifle down and leave that life behind. He dedicated himself to the world of medicine, helping others in hopes of redeeming himself for the guilt of his past. But some secrets die hard."
In a flashback tale 20 years in the past, we watch Kurt Harm and his bride of one year finally able to take their honeymoon, heading to Hawaii. We learn that he had been "in the Special Forces for six years" and held the rank of Captain with Delta Force. Even as he and his team is pulled back from R&R to take on a mission to Africa, he learns that his wife is pregnant. Life was good - until it wasn't. The mission went very bad due to some very incorrect intel and Harm knew he was done with his Army life. What he did not expect was that two decades later, what happened on that mission would change his life completely.
Leap back to the present and we find Harm now a very accomplished doctor specializing in cardiology with an impressive number of awards to show for his years in medicine. He is divorced with a grown daughter. His career was going strong and he was fully expecting to stay doing what he loved for the rest of his working life - then a man showed up with video evidence from that long-ago mission and the direction for him to take time off to do a little job for him and his superiors. That job would be to eliminate a man and it will not be the last such 'request'.