10 Horror Movies Based On True Stories (That Were All Lies)

Wes Craven's folk-horror is based on an investigation by ethnobotanist, Wade Davis, who ventured to Haiti after hearing about a dead local, Clairvius Narcisse, who was resurrected as a zombie through Voodoo.

As fascinating as this premise is, almost every aspect of Haitian culture is grossly inaccurate, since zombies and resurrection aren't a part of this spiritual practice. Voodoo focuses on healing, not summoning evil spirits and malevolent forces, as is depicted in the film.

Then there's the investigation itself. Although the real Wade Davis tried to find a logical explanation for Clairvius' alleged resurrection, The Serpent and the Rainbow only offers one explanation: black magic. Davis believed a paralytic poison called tetrodotoxin was used to place Clairvius and other Haitians in a mindless state, akin to the undead. But in the movie, it's believed the plant itself turns people into literal ghouls.

Though Davis' theories sounds reasonably grounded, pharmacological experts thought his findings were nonsense, to the point where were classified as "scientific fraud". 

Taking all that into account, it's safe to say The Serpent and the Rainbow is pure fantasy from beginning to end.