Mr. Sabin is a freelance agent.
That is really a misnomer in that Sabin does not earn a living as a private operative but it is nonetheless accurate because he definitely is acting as an operative in both of the two recorded adventures we have of him but he does so for his own reasons without an employer.
When we first meet him he is at a fancy restaurant having a late evening meal with a beautiful young woman. That was not noteworthy but the events as they were both leaving are. As he was preparing to enter the carriage to take them home, Sabin was the victim of an attack by a mysterious figure. The intervention of a third party was just enough to give Sabin a chance to strike soundly the assailant with his fancy walking stick, forcing the man to flee. The interesting aspect of this altercation comes in the attitude and reaction by Sabin. He was most cordial and appreciative to the helper but he was also extremely calm and collected; as he smoothly lit a cigarette, his hand was perfectly steady. It would have been impossible for anyone to ascertain how close to death Sabin had been moments before.
Sabin is described as being "well preserved" with "his little imperial and short grey moutached [being] trimmed with military precision". His hair is said to be almost white, "his age could scarcely be less than sixty". "His eyes, underneath his thick brows, were dark and clear, and his features were strong and delicately shaped. His hands were white and very shapely, the fingers were rather long, and he wore two singularly handsome rings, both set with strange stones".
All the above makes Sabin sound like a very interesting individual and indeed he is. It also, though, sounds as though Sabin should be seen in a positive light, something many who knew him would strongly disavow. As the man who tried to kill Sabin would say of him soon after, "There has never been a man or a woman yet who has not been the worse for knowing him. He is like the pestilence that walketh in the darkness, poisoning every one that is in the way of his horrible infection". The man hearing those words would pooh-pooh them instantly. He would later change his mind.