Czerny Clark is an agent with Blackthorn.
The official name for the organization is the Blackthorn Asset Group, a private special-operations company whose main client is the American government. That is, at least, the official story which has most people who knew of it, and that was a small number, thinking it mostly a mercenary clearinghouse. The extreme few in the know were aware that there really were no other clients; "originally funded by a sneaky line item on a pork-filled bill by Congress", Blackthorn functioned as a private company because it was "the best way to ensure ultimate deniability: the US government couldn't be responsible for something they had no knowledge of or control over".
The official intelligence agencies in the American community were apparently largely as in the dark about Blackthorn as the general public, one exception being the CIA and theirs was not a friendly relationship. "Blackthorn operated where they wanted, when they wanted, and the CIA only heard about them if they needed to use Agency assets. Beyond that, they were generally kept out of the loop, and that was what bothered the Agency people the most. The CIA preferred to be the secretive ones".
Blackthorn was founded by and run by a man named McHenry who was extremely good at recruiting only the very best operatives from other departments and largely from the military. "Blackthorn operators were the tip of the spear" and Clark was the sharpest of a very sharp group.
Clark is described as a "large brown man, son of a Russian mother and a Black GI father, Clark grew up in various military bases around the world." He had been a proud member of the highly elite U.S. Army Delta Force, stationed at Fort Bragg, when McHenry came to make him an offer. McHenry relates how he knew that Clark had what his organization needed but even McHenry had not gauged correctly just how good Clark would be at infiltrating a hostile area, eliminating the assigned target, and then getting out alive.
Clark's employment will change over time, some through his own desires and some through some major skullduggery which will cause Clark considerable trouble but one thing that will not change is that Clark is very good at completing a mission, no matter the chaos.
A colleague and ofttimes partner of Clark is Miriam 'Miri' Banks, a dirty-blonde woman with deep olive skin and a husky voice that seemed out of place from someone with her physique. Of all the other operatives at Blackthorn, she was the closest to being as good at her job of eliminating dangerous targets as Clark and, truth be told, it is safe to say Clark would not willingly make her an enemy.