10 Horror Movies You Didn't Know Were Based On True Stories

2007's Borderland follows three recent Texas college graduates who decide to head down to Mexico to check out some strip clubs and have a good time. While there, they take some mushrooms, drink, get into fights, and soon encounter a bloodthirsty cult that is determined to sacrifice a human, an act which they believe will help them with their drug-smuggling exploits.

This story is based on the life of American serial killer Adolfo Constanzo - who led a cult that was responsible for countless ritualistic killings - and the death of Mark Kilroy, a student at the University of Texas. Kilroy was tortured and murdered in a ritual by Constanzo's cult, with the leader telling his followers that Kilroy's sacrifice would make them immune to law enforcement, so they could smuggle drugs more easily.

In the film, Sean Astin plays an American character called Randall, a serial killer who is in cohorts with the cult. This character seems to be based on Constanzo, since the two even look (and dress) similar. As for Kilroy, one of the college graduates (a character named Phil) is tortured and killed in a ritual, which seems to be a representation of Kilroy's brutal real-life murder.