Ethan Shaw is an agent with the CIA.
Is and then was not too far into the first recorded adventure. Someone higher up did not want him to succeed and so sabotaged the mission. Then Shaw found himself disavowed in a hostile environment and locked away in a prison for who know how long.
Shaw had to figure it was nothing personal about the whole mess since he had not been an agent long enough to make the kind of enemy who would go to so much trouble just to land him in a foreign jail. Still, here he was potentially preparing to rot behind those bars so Shaw had to realize that it all was pretty personal to him.
That is when Julian Echo came to call with an offer. Echo wanted Shaw to work for him. He likely had come to the prison to get another inmate out, a man named , about whom other adventures have been written, but he took the time to make the offer of employment to Shaw as well.
Shaw was obviously confused by Echo and the job offer and all the things going on around him but being a pretty intelligent man, Shaw decided that whatever Echo had planned for him, being out of prison was better than in.
"We operate as ghosts, Ethan. We can only be as good as the wreckage we leave in our wakes, not the trails we leave behind. And you, kid, have a pretty big trail behind you right now."
When going undercover, "You're already out of place, simply by being someone pretending to be someone else."
"Most of [the intelligence agencies] are worried about getting the credit or shifting the blame, whichever seems more reasonable at the time."