Havana Syndrome is the claim that some enemy is targeting Americans with a futuristic weapon which is undetectable and which causes mental damage to the victim. It’s so-named because CIA operatives in Havana were the first ones to report it.
Since first reporting in 2017, there have been additional reports from around the world. The CIA has officially sought to frame the reports as mass hysteria at best, and a money-grab at worst.
60 Minutes has been reporting on it for some time, and a new book was written by two of that show’s editors: The Havana Syndrome: Secret Weapons, a Government Cover-Up, and the Greatest Spy Mystery of Our Time
Frustratingly, there’s no smoking gun. There’s a ton of circumstantial evidence — something absolutely happened to these people — but no one has ever caught the perpetrators in action.
The NSA apparently abstained from a report discounting the attacks, which the authors interpreted as them having eavesdropping evidence they didn’t want to reveal but that couldn’t go on the record against. And, in the very last chapter, the authors write of a meeting with an unidentified source that says the CIA bought one of the weapons on the black market, meaning they’ve lied for years when they claimed these reports were baseless.
The book is well-researched, but as I said, you’re not going to find any clear answers here. It might be a long time before the truth finally comes out.