Science experiments need replication and controls. They would both be in the same process. White room first, then dark room.
Possibly they don't remember being in the room? They have flash backs to it later?
Or they do go through the room, with some results, but then experience results after they leave?
They are both found on the beach/island after X hours? (48 hours?) The subdermal beacons went dark for that long, then reappear next to each other on a different island than the one's they were dropped off on, both were on different islands, found on the same third island.
They return to normal life, in different states, but end up needing to talk to each other about the experiences they are having.
They end up on a wild adventure to find the one who did this to them. They are being followed by someone, but never quite see them. They are seeing things that "aren't there" so they attribute the people following them to this new phenomenon.
The end? Unkown... ties to a new story? Most likely...
LA Thugs/Mexican Gangs
A retired pastor, a pastor of a large church, a priest???? Maybe not a pastor, maybe a spiritual mentor that doesn't work at a church.... hmm....
Book: White Noise
A phenomenon (Greek: φαινόμενoν, phainomenon, from the verb φαίνειν, phainein, "to show, shine, appear, to be manifest (or manifest itself)"), plural phenomena, is any observable occurrence. Phenomena are often, but not always, understood as 'appearances' or 'experiences'. These are themselves sometimes understood as involving qualia.
The term came into its modern philosophical usage through Immanuel Kant, who contrasted it with the noumenon. In contrast to a phenomenon, a noumenon is not directly accessible to observation. Kant was heavily influenced by Leibniz in this part of his philosophy, in which phenomenon and noumenon serve as interrelated technical terms.