Alan Llewellyn is a teacher.
According to the flyer I read of this interesting man regarding whether he was a "teacher, sleuth or spy? If you asked him, he'd probably tell you 'It depends.'". It goes on further to show that he "keeps his day job at Augustine Washington High School but confronts crises that are a ton more violent than kid fights in the cafeteria".
Having been in Special Forces for many, many years before leaving the military and taking a simple, "safe" job as a high school teacher, Llewellyn is quite accustomed to danger and to tricky situations. Both are good experiences to have had because Llewellyn's nature is to not look the other way when bad things happen or when someone asks for help, no matter who the person is or what the trouble is.
Of course, as we will find over time, when one of his former high school classmates and friends grows up to become President of the U.S. and that is one of the people sometimes asking for help, things can really get crazy quickly.