Real Name: Duane Alexander
AKA: Yuri
Actor: Lennie James (using his American accent), Ref:Jericho+"John," Person of Interest

Concept

Wisened, Hard-Core, Veteran Troubleshooter

Tropes

No problems with killing bad people, cutting off thumbs, or whatever it takes.
Smoothly and unapologetically deceptive in his dealings with non-Project persons; always has a backup story, and it's rarely/never true.
Extremely loyal to the Project, and Gabriel. Eventually stopped trying to uncover who Gabriel is.
"Knows where the bodies are buried," but reveals only what is needed when it's needed.

Yuri's true background and motives are shrouded in mystery. The only person (in the campaign) that knows his real background or identity is Gabriel.

Possible military experience (Spec Ops)
At some point, joins the CIA as a Paramilitary Operations Officer in the Special Activities Division (SAD) of CIA's National Clandestine Service (NCS).
Burned at CIA; on the run, effectively homeless
Recruited by "Gabriel," acting as a troubleshooter/investigator/man-on-the-ground in cases against white-collar criminal operations; designated Project Proteus.

B&E; Deception; Marksmanship; Hand-to-Hand Combat; Tactics; Espionage; Interrogation; Indomitable Will

Basically a combination of John-Person of Interest and Hawkins-Jericho
The original basis for this character was a super/mutant, an animal-based shapeshifter (like Manimal) codenamed Proteus, who was also a government agent.