It belongs to the genus Datura. It's better known as jimson weed, angel's trumpet, or more appropriately, devil's trumpet. The plant Datura stramonium contains a chemical called scopolamine:
Scopolamine has practical uses, for instance, preventing motion sickness. But, more importantly, it's a really dangerous drug that basically makes a person totally obedient to suggestion, while still appearing lucid, and not remembering anything while under its influence. In Columbia (and elsewhere), scopolamine has been used to get people to give over their money, belongings, and their body, all "willingly." Vice has a couple riveting videos, where Ryan Duffy visits Columbia to learn more about the nefarious uses of devil's trumpet.
I was in Florida earlier this year, and came across some sort of Datura. I took a flower, and showed it to a local at my hotel. He called it "angel's trumpet," and told me about how it was recently in the local news. Apparently, some teenagers made a tea out of it to try to get high. It ended up killing them.
Beautiful flower, though.