When first responders answered a 911 call to an upmarket suburban California home on March 26, 1997, they could never have expected the shocking scene that awaited them: 39 bodies, carefully arranged, laid out under purple sheets, each person’s feet bedecked with trendy black Nike sneakers.

The unforgettable crime scene images would soon be seared into the public consciousness as it emerged that the deaths were the result of a mass suicide by a cult known as Heaven’s Gate – who believed they were travelling by space ship to a higher level. Videos recorded by wide-eyed leader Marshall Applewhite, 65, are still instantly recognizable 20 years later – as academics, the public and authorities still wonder about the largest mass suicide on US soil.

The website for the group, which ran a web design company, remains active to this day, maintained by two surviving members who provide information to people curious about the Heaven’s Gate beliefs – although they insist, as the 20th anniversary of the deaths approaches Sunday, that the group does not persist.

‘The Group came to an end in March, 1997,’ they wrote in an email to DailyMail.com. ‘There is nothing to join but the information is timeless.’

When asked whether they were still connected to or in contact with their deceased former comrades, however, they said: ‘Yes, we are still connected to the Next Level, when they are’ – without elaborating.

First responders found 39 bodies carefully arranged at a mansion in a wealthy San Diego suburb in March 1997 - each with packed luggage at its side, five dollars and three quarters in the pockets

Leader Marshall Applewhite recorded lengthy video messages detailing the Heaven's Gate cult beliefs, which mixed biblical theology with elements resembling science fiction

The 39 adults were dressed in black, wearing Nike Decade sneakers, and took their own lives in shifts over three days, with members arranging the bodies of those who died before them

The group believed they were not, in fact, taking their own lives but would achieve a higher 'level' of being after being transported by a spaceship following the Hale-Bopp comet

The website masters are reportedly a couple who left to get married, which was against Heaven’s Gate rules, but retained their association – and shared beliefs – with the group, even allegedly fighting to take possession of the items the late members left behind. They refused to confirm this information to DailyMail.com or divulge any other personal details. They did, however, say that they look forward to being reunited on another ‘level’ with the members who departed this world in 1997.

‘We hope to have the opportunity sometimes in the future but we do not know when that will happen,’ they told DailyMail.com. ‘Probably in our next reincarnation on this planet.

‘The simple understanding is that there is a real, physical level above the humans one here on earth. It is not a spiritual existence. It is real individuals, in real bodies, in real crafts taking care of the issues of their planet. The Next Level, as it is called, created this planet and all the life on it. The Next Level are the care takers of not only this planet but all the systems of the universe.

‘From that, all the other understandings follow. They periodically come down to this planet to check in on this civilizations development. The last time they took a very close up observation, in human form, was from about 1972 to 1997. The time before that was 2000 years ago. At those times they talk to those interested about the opportunity of the Next Level and how a very select few can enter into it only after a long period of transition and instruction.’

The group, which ran a web design company, maintained a website full of writings and videos about their beliefs which is still kept active by two former members

The bodies were discovered after a former member received a message from the group, mailed before their deaths, then went to the house and alerted authorities

And while the cult’s unorthodox belief system and mass suicide shocked the world in 1997, it had been decades in the making.

The cult first began when Applewhite, a divorced father-of-two and son of a preacher who had tried his hand at everything from acting to running a deli, met nurse and middle-aged mother-of-four Bonnie Nettles in Houston in the early 1970s. They shared an immediate bond over their mutual interest in both biblical theology and the occult, and they began cobbling together their own belief system – eventually deciding that they were the ‘two witnesses’ mentioned in the Book of Revelation. They believed they were prophets for a God who was really an advanced extraterrestrial, that individuals could advance to an evolutionary level above human, and that the world would one day be ‘recycled.’ The pair believed that Jesus had been sent on a similar mission by this same celestial being.

On New Year’s Day, 1973, they set off across the country to share their beliefs and eventually garner hundreds of followers from across a vast socioeconomic and geographic spectrum. They left their former lives behind, including their respective children; during their initial travels, they ran out of money and would stop at blood banks for cash or routinely skip out on bills. At one point, Applewhite spent six months in jail in Missouri for auto theft after renting a car and simply driving off with it – before Do and Ti eventually disavowed stealing.

Applewhite and Nettles called themselves Do and Ti, among other names, and created a strict routine and set of rules for their followers which regulated everything from bathing to food

Marshall Applewhite, left, was a musician and the son of a preacher who believed God was an extra-terrestrial being, while Bonnie Nettles, right, was a nurse and mother of four

They distributed fliers and even took out newspaper ads as they continued their cross-country proselytizing mission, picking up followers along the way. The group would shift in name, belief system and number over the years, but always under the leadership of Applewhite and Nettles, who called themselves Pig and Guinea, Bo and Peep and, most famously, Do and Ti – in a fantastically close, platonic relationship. At one recruitment meeting in Los Angeles, they reportedly said: ‘We are The Two prophesied in Revelation. God has sent us here as an experiment, so you might call us Guinea and Pig.’

Members were kept to strict regiments as the group moved across the country, sometimes living at campsites, other times renting houses with funds often taken from a follower’s trust fund. Anyone joining was required to leave behind family, friends and possessions (although the trust fund made the cut) and to abstain from sex, drugs and other worldly pleasures; by the time of his death, Applewhite and several other male members had been voluntarily castrated. Everything was regulated, from their communal clothes – including underwear – to the length of their bathing time (six minutes using one gallon of water) to the size of their pancakes. They were allowed to work regular jobs in their areas of specialties outside the commune, however, generating more funds for the cult – and at the time of the suicides ran a computer company.

Applewhite and Nettles believed they would be killed for their beliefs and rise again three and a half days later in a ‘cloud’ or UFO, after which the world would be destroyed.

The group was never targeted or threatened by the government or anyone else, however, skewing their predictions of achieving resurrection through murder. Nettles instead died from cancer in 1985, again shaking the core belief system. Applewhite altered his ideas and came up with a new revelation after astronomers sighted the Hale-Bopp comet and, in November 1996, a photo emerged which appeared to show an object trailing in its wake. Applewhite announced this was a spaceship which would pick up the remaining followers if they cast aside their earthly bodies.

At the mansion the group then shared in Rancho Santa Fe, California, a suicide pact was formed.

Over three days, the members consumed a mixture of vodka and phenobarbital poison with pudding or apple sauce, then tied plastic bags over their heads. Each was dressed in black shirts and sweat pants, brand new black-and-white Nike Decade sneakers and armbands reading ‘Heaven’s Gate Away Team.’ The bodies all had a five dollar bill and three quarters in their pockets along with packed luggage at their sides.

As each shift of followers died, the remaining members removed the plastic bags and arranged the bodies before taking their own lives. The final death shift consisted of two members, left with no one to remove the bags or neatly array the bodies.

The victims ranged in age from 26 to 72. Some had been in the group for 22 years; others had left and come back when their outside world lives hit speed bumps or they simply continued to feel the Heaven’s Gate pull; others had been members for just a few years. Some were parents who, like Applewhite and Nettles, had left behind their children. Some members were dreamers and drifters, while the occupations of others ranged from bus driver to ex-paratrooper to paralegal to journalist.

The Heaven's Gate victims ranged in age from 26 to 72, and some had been members of the group for as long as 22 years under the leadership of Applewhite

Marshall Applewhite, who was 65 when he took his own life, altered the group's beliefs many times over the years, ultimately decided a passing spaceship would pick up his followers

Members videotaped 'exit' messages before the mass suicide, which had been meticulously planned in advance to coincide with the passing of the Hale-Bopp comet

In addition to videotaped messages, Heaven's Gate prepared a press release for the media before ingesting poison mixed with pudding and apple sauce

They were discovered by another Heaven’s Gate member, Rio Di Angelo, who had planned to be the 40th body discovered in the mass suicide – right up until a few weeks beforehand, when he claims to have woken up with a feeling that he had something yet to do on Earth. So he left with the Applewhite’s blessing, he said, and after the suicides received a package with a videotapes and a map to the home where he would find them. He got a ride to Rancho Santa Fe, went inside and then alerted authorities.

The group had planned meticulously before they ingested the fatal concoction, making ‘exit’ videos explaining why they were making the decision – as well as preparing a press release for the media.

‘By the time you receive this, we’ll be gone – several dozen of us,’ it read. ‘We came from the Level Above Human in distant space and we have now exited the bodies that we were wearing for our earthly task, to return to the world from whence we came – task completed. The distant space we refer to is what your religious literature would call the Kingdom of Heaven or the Kingdom of God.

‘We came for the purpose of offering a doorway to the Kingdom of God at the end of this civilization, the end of this age, the end of this millennium. We came from that Level, that time, that space, and entered this one. And in so doing, we had to enter human bodies – which we did, for the most part, in the mid-seventies.

‘Now it was time for us to leave those bodies (vehicles) – bodies that we borrowed for the time we were here (by previous arrangement) for this specific task. The task was not only to bring in information about that Evolutionary Kingdom Level Above Human, but to give us the experience of working against the forces of what the human evolutionary level, at this time, has become. And while it was a good learning experience for us, it also gave all who ever received knowledge from that Kingdom an opportunity to recognize us and this information, and to even move out of the human level and into the Next Level or the Next Evolutionary Level, the “Kingdom of Heaven,” the Kingdom of God.

‘The Kingdom of God, the Level Above Human, is a physical world, where they inhabit physical bodies. However, those bodies are merely containers, suits of clothes – the true identity (of the individual) is the soul or mind/spirit residing in that ‘vehicle’. The body is merely a tool for that individual’s use – when it wears out, he is issued a new one.

‘No one can enter the Kingdom of Heaven by trying to live a good life in this world, and then, thinking that when this world’s life takes your body, you get to “go to heaven.” The only time that Next Kingdom can be entered is when there is a Member or Members of that Kingdom who have come into the human kingdom, incarnated as we have, offering clarification of that information.’

The website maintainers told DailyMail.com that they had been in the group for 12 years and ‘joined immediately after attending a meeting that Ti & Do held. Their truth was undeniable.’

They said interest continues in the group’s complicated belief system mixing traditional theology with its sci-fi-esque tenets.

‘We get an average of about 10-12 emails a day,’ they said. ‘They come from all over the world. We sell several books a year and give away about 40 or so free VHS tape sets. There is no dominate geographic area. More tapes and books go out domestically because of the cost of shipping internationally. The demos on this are very diverse.’

The group lived communally in a mansion in Rancho Santa Fe, outside of San Diego, and some members maintained regular jobs outside of the home

Rio Di Angelo, who says he planned to join the Heaven's Gate members in the mass suicide up until a few weeks beforehand, discovered the bodies and alerted authorities

The March 1997 mass suicide was the largest to take place on U.S. soil in history and made headlines around the country

Survivor Rio Di Angelo, who was selected to discover the Heaven’s Gate bodies, also continues to espouse the group’s beliefs and remains in occasional contact with the website moderators, they say. To coincide with the tenth anniversary of the suicides in 1997, he released a statement, insisting: ‘I’m glad to be alive and planning to stay that way. I have a wonderful life with purpose. I am alive NOT because I rejected anything about Heaven’s Gate. I am alive because I have discovered something so extraordinarily important to the world that it needs to be passed on to you in its most true and accurate form from ME.’

He went on to explain the tenets of Heaven’s Gate, saying: ‘When there is a Representative from the Level Above Human (Heaven) here on Earth, you will be drawn to Him and His mission. You then will be taught the final lessons in a type of finishing school. These important lessons enable you to know how to create a Soul. A Soul is different than a Spirit. A human Spirit is Earth bond only. A Soul is “you” conscientiously choosing to evolve into a new creature that has the non-human ingredient needed for transition into the Level Above Human.

‘That Representative becomes your teacher and is the only one who can usher you into the higher level of existence. He knows how because He’s done it before.

‘This is my understanding of the mission that Jesus started. This is why He was here and said he would return.’

Confirming his three-year membership in Heaven’s Gate, he said: ‘I know everything worth knowing about them and I can say with absolute, undeniable certainty, that Heaven’s Gate was indeed “The Second Coming of Jesus.”’

He said: ‘I am against suicide and so was the group. What happened to Heaven’s Gate was an “EXIT,” “The end of the Spirit reincarnation process and the beginning of life as a Soul in the Level Above Human.”

‘They “EXITED” their bodies (vehicles) and are now with their Guide and Teacher in the Spirit world (the Valley of the Shadow of Death) helping mis-guided Spirits before their ascension.

‘I am here to bring you the truth and to clarify information for you to examine. Also, to help with understanding the next steps, after the “Second Coming,” if that is your choice. I am not here to convince you to do anything or to believe any of this. If it speaks to you, use it. If not, go on.’