Chapters 2-5 looks at agent characters and campaigns at different levels by viewing them through the lens of groups found in M&M's Freedom City campaign setting.
Chapter 2 focuses on city police, namely FC's Star Squad, the elite cops who get to fight supervillains when the heroes aren't around. The Squad's history and procedures are listed, along with some ideas for adventures. Following this, there are some ideas for police-themed campaigns in general, including common archetypes bound to show up (like the gruff but loveable desk sergeant).
Chapter 3 looks at agents on the Federal level, specifically FC's answer to SHIELD- AEGIS (get it? AEGIS is a kind of shield! Yeah.). Like the chapter on Star Squad, the agency's background, composition, and noteable personalities are listed. Unlike the previous chapter, however, it just focuses on an AEGIS themed game. This chapter would've been a bit more useful if they gave a brief note on other federal agencies, such as the FBI or ATF, but this chapter was already pretty long as it is. As it stands, this chapter certainly gives enough ideas if you want to do an "Agent of ______" series where your spy or commando faces off against supervillains, cults, aliens, or what-have-you.
Chapter 4 looks at Freedom City's UN law enforcement group, UNISON. While this chapter is very brief, it does expand what the rest of the world in the FC universe thinks of superheroes and alien invasions and so forth. Plus, the notes are making UNISON agents are generic enough that they can serve as a rule for making any kind of global peacekeeping commando or spy.