Stephanie Relfe wrote about her theory that many people get abducted from hospitals and thrown into deep black programs - some of her ideas seemed quite fanciful to me when they first appeared about 20 years ago, but in light of what we know now…
here is one of her books where she discusses it:
https://archive.org/stream/steakandpotatoes5_gmail_Mars/221993563-The-Mars-Records-1_djvu.txt