[ NANO ] PREP WEEK 3 - Outlining Your Story ( also , programs you may want to get and learn in advance )

So, my problem is that I'm not exactly sure how mine will end yet. In fact, I'm not even set on the middle, the beginning, or many major plot points, but could use some feedback. 
 
 Set in a small rural town. Starts with a scene where the main character is offered a drug. The character tries the drug, has a rather bland experience compared to everyone around him, who enjoy themselves and it seems to act as a mix between a hallucinogen and something like ecstacy. Main character decides they must be immune to this drug after trying it more. 
 
 Eventually, nearly everyone in the town becomes hooked on the drug. The effects change after dependence sets in and the users become lethargic, violent, etc. This results in fights, people who neglect themselves or others, and overdoses. 
 
 In addition to this, the main character has dreams/nightmares ( or flashbacks ) about a relative who died mysteriously years before at a party. The autopsy was inconclusive but since the relative was underage, the man throwing the party was arrested and jailed or sued for wrongful death or manslaughter or something. 
 
 This is where I'm stuck, somewhere towards the middle or end. I'm thinking of branching a couple of ways with this. 
 
 One branch being that the man who was arrested has been released and is spreading the drug to others and recruiting them into a drug ring of some sort, possibly related to a cult. Or maybe he is still imprisoned but has connected with someone unexpected outside of prison in order to create and distribute the drug and run the drug ring/cult. 
 
 Another branch that I have n't decided on is this: Is the cult just a bunch of crazy drug freaks looking to turn a profit and keep their minions under control? Or do they serve some kind of being that actually exists? I was thinking that if it's the second, maybe the being is actually the source of the drug, and is waiting/sleeping/plotting to take over the world or otherwise enslave/kill humanity. 
 
 So, basically: do I go the realistic route or the fantastical horror route with the later parts of the novel? 
 
 Just writing this has helped a bit, I think, but I'd still appreciate some feedback, though this might end up being something that I do n't completely decide on until the earlier chapters are written.
