Before Jackie Speier headed into the jungles of Guyana to investigate living conditions in a town created by Peoples Temple founder Jim Jones in 1978, she wrote her parents a letter that she tucked into her desk drawer.

“Mom and Dad, I love you,” Speier, now 74, reads from her note in an interview with USA TODAY. “Should anything happen be proud because my life has been full of the love you have given me. I have no regrets. Love, Jackie.”

As a footnote, Speier, then a 28-year-old legal aide to California Congressman Leo Ryan, included mention of a $1,000 life insurance policy.

Ryan’s constituents communicated their concern about the makeshift dwelling dubbed Jonestown. So Ryan, Speier, journalists and family members of its more than 900 American residents traveled to the country on South America’s northern coast, uninvited by the charismatic and erratic Jones. Their trip – and the resulting poisoning of hundreds of members with a cyanide-laced fruit drink – are the focus of “Cult Massacre: One Day in Jonestown.” a National Geographic docuseries now streaming on Hulu. The three-part project features interviews with Jonestown survivors, journalists who covered the journey and Jones’ son, Stephan, once a resident of Jonestown.

After members of the church decided to flee Jonestown, other congregants targeted them on an airstrip, opening fire on the defectors and visitors. Speier took shelter behind the wheels of a plane and pretended to be dead. Still, she was shot five times at point-blank range. Five died on the tarmac, including Ryan. That same day, more than 900 Jonestown citizens died at the urgency of Jones.

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“It's hard to believe that that actually happened,” Speier says. That “a congressman who was attempting to protect his constituents would be gunned down in the manner that he was, that the members of the press would lose their lives, that a number of us would be wounded because there was a madman whose ego was not in check and who, as a megalomaniac, wanted everyone to suffer.”

Who was Jim Jones, founder of the Peoples Temple?

Jones established the San Francisco-based church that performed acts of service throughout its community and embraced members of all races. In 1974, he moved to an area of Guyana that he dubbed Jonestown, which he promoted as an idealistic place to run his church.

“What you see in the media about my father,” Stephan Jones says in the documentary, “one who didn’t experience the temple can’t help but think, ‘Why would anybody follow that guy? There must’ve been something wrong with these people from the start.’ Dad was dynamic at times.”

Grace Stoen, a member for six years says, “I would do anything for Jim Jones, in the beginning, anyway. But over time, Jim started behaving strangely.”

During a meeting that ran late into the night, she says she fell asleep and woke up to see Jones holding a gun to her head. “He goes, ‘I love you very much, but don’t fall asleep because I will kill you,’” she remembers.

“A lot of my father’s craziness was well hidden for years,” Stephan says, “but he was as nuts as anybody gets.”

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People held against their will in Jonestown

Stephan says that once people arrived in Jonestown, his father confiscated their passports. They’d need Jones’ permission to travel.

On the first night of Ryan’s Jonestown visit, on Nov. 17, 1978, NBC journalist Don Harris received notes from two Jonestown residents saying that they wanted to leave.

When Harris showed one note to Jones, the preacher said, “People play games, friend. They lie.” He insisted people could come and go as they please.

Speier says she brought Ryan’s constituents letters from their parents, but the congregants didn’t want to engage with them. “They all seemed almost like they were automatons,” Speier tells USA TODAY. “They all were young adults. They were all getting married to another member of the temple.”

Temple members murder five at Port Kaituma Airstrip

The next day, 15 congregants asked to leave Jonestown, according to the documentary. About 30, including Ryan, Speier, members' kin, and reporters waited anxiously on a tarmac to return to the United States. Ryan waited, wearing a shirt stained with the blood of a temple member who attempted to stab him to death earlier that day.

While the evacuees were boarding, a trailer of gunmen from the temple arrived and began firing. NBC videographer Bob Brown was killed; so was Ryan, NBC’s Harris, defector Patricia Parks and photographer Greg Robinson. The next morning, a Guyanese Army helicopter arrived and secured the runway. The survivors were flown to Georgetown, the capital, and from there to Washington on a U.S. Air Force plane.

The Jonestown massacre, hundreds poisoned with cyanide concoction

Back at Jonestown, Jones informed parishioners of the congressman’s death. He also told residents that the defectors made it impossible to resume life as usual. “There’s no way to detach ourselves from what’s happened today,” Jones said in an audio recording. “If we can’t live in peace, then let’s die in peace because we are not committing suicide. It’s a revolutionary act.”

A woman is heard pleading for the life of the children, but Jones chillingly told her, “It’s too late. If you knew what was ahead of you, you’d be glad to be stepping over tonight. There’s nothing to death, it’s just stepping over into another plane,” he said. “Stop this hysterics. Die with some dignity.”

David Netterville, with the U.S. Special Forces, says he found several victims “that you could tell they had been held down and had been forced to either drink (the poison) or had been hit with a syringe in the back of the neck.”

According to the documentary at least 153 men, 452 women and 302 children perished at Jonestown.

Jones died from a bullet to the head.

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