Ordinary person finds themselves in an extraordinary situation – one of the standard story types. In which case, the scenario is key, the full story can be anything.
A simple hacker (with a heart of gold) finds their way into the modern version of Bohemian Grove – a meeting of right-wing, religious, conservative, nutjobs with a Masonic bent who worship a being who is more than a bit satanic. Future and former US presidents are present.
These days, because their secret got out (a little, conspiracy theory mostly), they meet via virtual reality, and our protagonist stumbles upon it. Think Eyes Wide Open meets War Games. Use your imagination for the rest. Involve David Icke.