Reading the front page of the manual reminded me of the brilliant dystopian sci-fi film Equilibrium. It's a very similar world, where peace has been achieved through suppressing people's creativity and emotion by force. The people have injected themselves with drugs to stop them from feeling emotions and committing "sense offenses".
That's a great example of the Theme. I had forgotten about this movie. I always liked the "Gun-Kata" sequences as well. This is my 3rd favorite Bale flick. (ie. 1.Batman, 2.Reign of Fire, 3.Equilibrium)
The ability to Turn a Hunter is an interesting one...Maybe the Agent wouldn't have to reveal his self if it was the "turned" hunter who would have seen him. The Hunters would need some way to counter this after a turn or two tops otherwise it becomes too unbalanced in the Agents favor. Maybe the "turning" is temporary and it will take D2 turns for the Chemicals to be neutralized in the Hunters bloodstream.
Which probably has the same net game mechanic effect as Stunned. But might be an interesting "Specialty Equipment" that could be fired(?) at a Hunter.