You've never heard of scopolamine. It's synthesised from plants, like cocaine. It even looks exactly like cocaine. But unlike the restricted drug, it'll turn you into an insane zombie and probably kill you. There's a reason they call it "The Devil's Breath."
It's hard to even call scopolamine a drug, in the usual sense of the word -- nobody is going to pass it around at a party or buy it at a club. But criminals will use it to steal all of your worldly possessions, Nazis used it for interrogations, the CIA tested it as truth serum and indigenous Colombian royalty would have their families coerced into being buried alive under the influence of the stuff.
VICE sent a crew down to the jungle to investigate, and turned up some pretty brain curdling stories. Sadly, when they actually do get their hands on the stuff, they chicken out and flush it down the toilet at the end, like a scene from Cops. Though by that point, it's hard to blame them.