Complex sentence: The series centers on an intelligence analyst at a national think tank in New York City called the American Policy Institute (API), who discovers that he may be working with members of a secret society that manipulates world events on a grand scale.
Split into simpler sentences: The series centers on an intelligence analyst working for the American Policy Institute (API) in New York City. He discovers that he may be working with members of a secret society that manipulates world events on a grand scale.