Sorry if this has been mentioned before!
Netflix has a documentary series 'Web of Make Believe: Death, Lies and the Internet' and it has an episode on the murder of Seth Rich, an employee of the Democratic National Committee which naturally led to conspiracy theories. There's a weird bit where the Russian intelligence services capitalised on that to put out fake information too which is interesting given that the conspiracy nuts believe anything blindly (not sure if this happened in this case, but I'd bet that it does) but could be being 'played' by other Governments to cause division and achieve some political aim. Quick edit - it just sort of goes through the whole “life cycle” of this particular conspiracy if anyone is interested in that
There's also some stuff about why people format conspiracies - people naturally look for patterns to explain why things are happening in the world, especially when it's hard to come to terms with those things which is why these conspiracies are often related to such heavy topics