In March 1997, 39 members of the cult were found dead at a mansion near San Diego.
A former Heaven's Gate member is looking back on the time he spent with the cult 20 years after dozens of its members committed suicide together.
The man, who goes by the name Sawyer, told Inside Edition that he spent 18 years with the cult, reaching the rank of "overseer" before leaving in 1994.
He recalled his conversations with the leader of the cult, Marshall Applewhite, who was known by his fellow followers as "Do."
“He said that there wasn't a day that went by that he didn't think of himself as insane,” Sawyer said.
Applewhite founded the group in 1974. In March 1997, he and 38 other members were found dead in their beds in a mansion in Rancho Santa Fe, near San Diego in California. The 18 men and 21 women were all dressed in identical black clothing and sneakers and were covered with purple sheets.
It emerged that Applewhite was somehow able to talk his followers into consuming a toxic mix of vodka and chocolate pudding or apple sauce that was laced with barbiturates. Some also had plastic bags pulled over their heads.
Applewhite told them the comet Hale-Bopp was being trailed by an alien spacecraft and, if they died, they could board it. He said that after their deaths, they would be transported to a new level of existence.
Reporters were stunned when they gained access to the mansion following the mass suicide. They found blood stains and splatters across some of the rooms.
The bunks and shrouds discovered at the mansion are now on display at the Museum Of Death in Hollywood, California. Mannequins wear the actual clothes taken from some of the bodies.
The website for the cult is also still working and looks just like it did decades ago.
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Professor David Taylor, who has studied the cult, told Inside Edition: “Everybody's wearing exactly the same kind of uniform."
"They wore drab loose clothing to minimize men being attracted to women and vice versa," he added.
He pointed out one of two different patches that they designed for the suicide event. "It says 'earth exit,' which indicates their intention," he said.
Nine of the men inside the cult castrated themselves “by their own volition," he added.
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