John Vedders is an agent with American Military Intelligence.
I use that nebulous term instead of something more definitive because the recorded missions that we have of him to follow leaves a bit of confusion in their telling. When we first watch Vedders in action, he comments that he worked for the U.S. Intelligence Corps. Another person adds that "the army intelligence needs you" so if this Intelligence Corps is an actual department, it is certainly connected to the War Department (later changed to Department of Defense). This seems to be confirmed when in the second adventure, Vedders calls it Army Intelligence which is a lot less misleading. Unfortunately, the third assignment we watch, he is said to work for the American Intelligence Service. Following that for the remainder of the tales, it is just identified as Miliary Intelligence, in which he holds the rank of Captain. It all sounds a tad haphazard but then again, given the government's love of changing things that did not need changing, it like is all the same.
We watch during our initial meeting with him as he looks in the mirror and sees a face that was accurately described as giving "a distinctly sinister appearance" but as we read further, we find it is all part of a terrific disguise Vedders has created for an undercover mission he is about to start; said look being the result of a particularly impressive skill at makeup. This talent will be something he will make use of more than once in the recorded adventures we have with him and he will be called a master of disguise by one of his opponents.
Quite telling about the life that Vedders leads and the work that he does as a field operative is the fact that the man he is making himself look like is on his last hours alive having been shot by Vedders just before we encounter him. "I hated to do it", he tells a colleague, "but I shot to kill. A single life - a half dozen lives - what do they mean when an international catastrophe can be averted? Who knows? I may be next."
The business that Vedders is in is a very violent one as we find out immediately. In the first pages of the first adventure, we learn he has just shot a man soon to die from that wound, he abducts and waterboards an American general and war hero who has turned traitor, and he injects adrenaline into an enemy guard bringing about his demise. Then he starts to get busy.
Vedders has been in the spy game for quite a few years, based on the fact that he runs into a notorious German former spy with whom he had crossed swords 16 years previously. This puts his entry just after the end of the Great War and places his age as likely in his late 30s. We learn nothing of his home life so it is not unreasonable to believe he in essence has none - the man is married to his job.
Which does not mean that Vedders does not have an eye for the opposite sex because he clearly does. In addition to a pretty girl here or there to catch his eye, Vedders has several interesting go-rounds with one of the most deadly operatives to come out of Central America, freelance spy Leone Mendez, described as the most gorgeous woman he had ever known: "dark, exotic looking but ravishingly beautiful". "Whenever she left a country there was scandal." That is the given word on this woman who seemed able to enchant and seduce any man at any time. She occupies his mind for a tad, leaves the scene for a long time, and then makes a wonderful return to show she is just as deadly, and enticing, as ever.
- After slapping handcuffs on the seductive Leone Mendez, Vedders apologizes, "Pardon my roughness, Leone, but a man in love with a woman - or his own life - can't stand on ceremony".