A documentary looking back at Jim Jones and the massacre in Jonestown, Guyana warns of cult-like devotion to demagogues.

Forty years ago, a self-styled holy man named Jim Jones oversaw the mass slaughter of nearly 900 members of his “church,” the Peoples Temple. A new documentary sheds light on the man and the people, examining the social and political motivations that led to this tragedy.

Jones and his followers died on Nov. 18, 1978, at their utopian community in the South American jungle, following his instruction to drink poison. It has since become the prime example of the dire consequences of cults, crowd mentality and single-minded devotion to a religious or political leader.

The new four-part documentary series “Jonestown: Terror in the Jungle” premiered this Saturday on SundanceTV. It featured testimony from Jonestown survivors, Jones’s now-grown sons, and author Jeff Guinn, who wrote the 2017 book The Road to Jonestown.

Who Was Jim Jones?

Guinn recently sat down with Yahoo Entertainment to paint a clearer picture of how the Jonestown tragedy transpired, drawing parallels that he sees between Jim Jones and a leader like President Donald Trump.

To Guinn’s surprise, when researching for his book, he discovered that Jim Jones was a great leader in the American civil rights movement. Jones and his wife almost single-handedly ended total racial discrimination in Indianapolis, which was one of the most segregated major cities in America.

Secondly, Guinn believed that Jones’s 900 followers were actually “intelligent, talented and socially committed people,” who truly believed in what Jones advocated: a movement that appealed to social change and “to make the world a better place.”

Jones also offered basic and helpful amenities such as free clothing and food to those in need, and even marriage counseling.

However, Guinn pointed out that Jones got increasingly bizarre in his behavior, yet the transformation was gradual enough to go undetected by many followers.

Mass Suicide or Mass Murder in Jonestown?

Tragically, many of the victims were not complicit in drinking the fatal poison either. There were armed guards all around the pavilion in Jonestown, and people who objected were held down and forcibly injected. Therefore, it was as much a mass murder as a mass suicide.

When asked directly about parallels to the current president, Guinn explained that all religious and political leaders are demagogues to some extent, using fear and separatism to obtain the loyalty of followers.

“The most obvious ones are they identify current social problems, but they exaggerate the danger,” Guinn told Yahoo Entertainment. “[And] they try to cut them off from other opinions and voices. They will always first attack the media, then they will try to separate people even from family and friends. Jim Jones fits that to a T, and I think people need to ask themselves: is there a lesson here for the present day?”

Jones has also been compared to Nazi leader Adolf Hitler, but with a notable difference: instead of appealing to people’s worst natures, Jones promoted values like selflessness and sharing in the communal lifestyle he aimed to build with his followers.

“Jonestown: Terror in the Jungle” premiered on Saturday on SundanceTV, but will air in repeat and can be viewed online here.