Would the FBI sit idle while a crime was being committed?

[The Backlash Cometh]

Okay, maybe that's the wrong question to ask, but, here's the scenario:

Let's say that you lived in the heart of a red county, and you know the locals are not known for playing fair. So, let's say that they're using their good ole boy networks to keep an eye out for anyone that might cause them trouble. Their eyes and ears would be someone monitoring mail coming in or out; or someone monitoring e-mail at the server level. These are just examples. And let's say that someone was a thorn at their side and they decided to play some dirty tricks on them. If the FBI picked up conversations from them setting something up like, interference of business or a potential break in, or some other kind of harrassment via the phone, how should the FBI respond? And how do you think they'll respond?