Just a few questions so I can wrap my head around the concept in action a bit better, if you don't mind.

1) Will you be playing a PC as well or will you just GM aka play NPCs (is Donnelley an NPC or PC)?

2) How will an investigations be played out? 
- Will you be placing clues/evidence somehow withing the RP? As a kind of [Player: I investigate the closet | GM: You find EVIDENCE] [i]player action -> GM answer -> player reaction[/i] formula that many tabletop games use?
- Will dice be involved? If so, how dice-heavy is this supposed to be? (E.g. only combat is a quick die roll vs "roll a die to determine whether you can see anything through the muddy window")
- Also, if dice should be involved, are we following a certain system? Perhaps the tabletop game Delta Green has a dice system?
- Is the investigation fully GM-driven (as in the GM decides the clues, evidence, bad guys, hurdles, etc.)? I'm assuming this might be easiest

3) Should PCs be team members of years already or rather new recruits or anything goes?
- If new recruits are allowed/wanted: Should the PCs know anything about the 'occult' yet or are they supposed to be clueless in the beginning? 

4) Can/Should the players also add to the occult lore of this world by creating their own (within the PCs backstory for example)?

Sorry to spring all of those questions on you in a simple Interest Check ^^ Feel free to take your time answering them or to gesture me gently out the door xD