Beck Casey is a college professor.
He is also an employee, on apparently a contract basis, of the CIA. He is not a trained agent qualified to go undercover to extract secrets or remove people. He is an academician with a particular set of specialties that makes his knowledge quite useful to the Agency. That does not, however and unfortunately for him, mean that life and the powers that be do not through him into situations where some actual training would have been good to have. Luckily for Casey, he is a very smart individual.
By disciplines, Casey has a couple of PhD's to his name, entitling him to be called Doctor though he prefers things less formal. He is an expert in Sociology and History and came to the attention of the CIA while working on a Master's writing a thesis on the ramifications to world history of catastrophic plagues. While the book that he created never was published publicly, it was read by quite a few in the halls of government and opened the door to a career. It detailed in frighteningly accurate detail how governments would normally react to sudden and harsh conditions and how the people would then respond to those reactions, and vice versa.
When we meet him, he has officially left that occupation to become a sort of travelling professor, invited to teach a semester at one university and then move on to another. It was while preparing for the start of yet another session of lectures that Casey is brought into the fold when another crisis arises that falls within his area of expertise.