With having to leave the Commission for a year while things cool off politically, Mark finds that the Church has loaned him out to the FBI, who have been trying for years now to get an experienced monster and demon expert in their newest division, to help train and educate the agents there on just what they will be facing. Finding out that Mark actually is one of those very monsters has made them want him even more; not just for what he can bring to the table, but because they do need to check off that newest minority checkbox, even if no one knows they exist.
Mark doesn't mind the new assignment, being closer to home, it means it will be easier to visit with family, and the agents all seem nice enough. Plus the FBI has a bigger budget and gets a lot nicer toys than Mark is used to. However, while Mark knows how to deal with devils, demons, and even the nastier monsters out there, he doesn't know anything about how to deal with a sociopath werewolf who has gone full psycho and started to murder co-eds.