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.
But the President calling is getting ahead of things a tad because the Chief Executive does not approach Llewellyn for help until the third adventure. The first two non-teaching gigs came about for other reasons and set the scene nicely for why Llewellyn would be so open to the call. Still, when the Big Man does call, Llewellyn's life changes quite a bit.
One thing that does not change, luckily for him, is his home life. He is married very happily to Maria, "the love of his life", and is the father of thirteen-year-old Elizabeth, "the other love of his life".
Llewellyn definitely has a sense of humor. When an old acquaintance calls and asks in passing how the 'teaching business' was going, he responded, "Very short hours, stress-free and big bucks."