An aging FBI agent (Harry Watson) from the Phoenix office is sent into a deep cover operation in an adult (55+) community in the Chicago suburbs where it is feared a group of ex-mobsters in the Witness Protection Program have begun to discover each other and "reorganize." As Harry is on his own, when the gangsters he is supposed to be observing begin to die, he reaches out to his friend, Chicago-based Private Investigator Justinian Kase for assistance and technical support. Between them they find unexpected twists as they solve the mystery of the Oldest Don.