What if an ancient civilization could have predicted the future? And calculated the end of time?
Some people say the Mayans, who thrived thousands of years ago in what is now Mexico and Central America, did just that.
The ancient Mayan calendar, say so-called "2012'ers," explains that time itself began about Aug. 11, 3114 B.C. and will end Dec. 21, 2012 -- the winter solstice.
"I believe the Mayan calendar was based on some good astronomy," Lawrence Joseph, author of "Apocalypse 2012," told ABC News. "They had a sense of timing. What I believe about the Maya was they were really good at knowing when. They weren't so good at saying what's going to happen."
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Joseph imagines a doomsday scenario not unlike a Hollywood movie due out this month: "The Road," based on Cormac McCarthy's Pulitzer Prize-winning novel.
A trailer for the movie sets the scene: "It is cold and getting colder as the world slowly dies. No animals have survived. And the crops are long gone."
McCarthy is vague about what caused his apocalypse.
But Joseph believes ours will come from solar flares -- bursts of radiation from the sun that will apparently peak at the end of 2012, penetrating the Earth's magnetic field and scorching the electrical grid.
"Over 130 million people in the United States alone could be without electricity for months or years," said Joseph. "And that just doesn't mean no telecom. It means no water, because the pumps are electric. It means no gasoline because the pumps are electric. No refrigeration."
Joseph said it "absolutely is very difficult" to live with the notion that everything we enjoy in the modern world could come to an end.
"I make jokes," he said. "I whistle in the dark. I have two young kids. And life has been good to me."
What does any of this have to do with the Mayan calendar?
"I don't know," said Joseph. "It is a coincidence that is striking and perhaps it's significant."
John Major Jenkins, author of "The 2012 Story," explained the calendar.
"December 21 of 2012 is the last day of the 13 cycles of this calendar, called the Long Count," Jenkins said. "And this calendar was invented about 2,100 years ago in Southern Mexico."
Tortuguero Monument No. 6
In search of answers, ABC News headed to southern Mexico, and then deep into the Central American jungle, to a place where it's easy to imagine a flood lasting 40 days and 40 nights. We searched for clues amid the ruins of the ancient Mayans.
Our guide was archaeologist Christopher Powell, who helped with some of the most important excavations of a civilization that mysteriously vanished more than 1,000 years ago.
"I consider it a great mystery, and one that I'm willing to see out with an open eye," Powell said.
The Rosetta Stone for 2012'ers is something called the Tortuguero Monument No. 6, a collection of hieroglyphics unearthed in the 1960s and promptly scattered to the four corners of the globe.
One fragment is kept in the bowels of New York's Metropolitan Museum. The museum would not allow us to film it.
A good chunk of it is in the Carlos Pellicer Museum in Villahermosa, Mexico. When we visited, the museum was closed due to flood damage.
The two remaining fragments have been missing for decades. Last photographed over 40 years ago, these two pieces are the key to unlocking the secrets of Tortuguero Monument No. 6, experts say.
A few years ago, David Stuart from the University of Texas-Austin translated the texts and set off a firestorm.
Jenkins gave ABC News a brief explanation:
"It's basically saying that the deity Bolon Yokte-Ku appears on Dec. 21, 2012, and he descends and he performs a ritual."
Powell said the hieroglyphics forecast the distant future.
"It goes several hundred years into the future to 2012, Dec. 21," he said. "It says 'and then it happened!' And then the verb is missing. It's eroded!"
Powell guided us to the Tortuguero cement works, not far from where Monument No. 6 was found.
He said we don't "really" know what the artifact's message is.
"Whatever that verb was, it's completely missing," Powell said.
That missing verb has opened a Pandora's Box of New Age prophecy.
'We Did Have a Chat'
In New York City, Daniel Pinchbeck presides as the hipster guru of 2012. Pinchbeck styles himself an urban shaman, seeking to solve problems like globalization and climate change by tapping into the lost wisdom of the ancients.
Does he think the world is coming to an end?
"I think a world is coming to an end," Pinchbeck said. "You know, the mind-set of this, you know, post-industrialist, materialist culture.
Pinchbeck claims that during a vision quest, an Aztec god told him to speak out about 2012.
"This time is this time of transformation," he said. "It's the best hypothesis I have come up with."
And Qetzalcoatl himself came down and told Pinchbeck.
"We did have a chat," he said.
Pinchbeck is just the tip of the pyramid. In Mexico, we met a Canadian woman, Star Johnsen-Moser, who believes in the psychic power of crystal skulls.
She's pretty excited about 2012.
"For us it's a time of great transformation," said Johnsen-Moser, the director of something called the Cahokia Mysteries School of Cosmic Education. "We choose not to focus on the prophecies of doom and gloom and frustrations because those are not very good thoughts to project on our Mother Earth."
Atop of the Temple of the Skull in the Mayan city Palenque, she gave us a dramatic demonstration, a ceremony to channel the power of her crystal skulls.
For Johnsen-Moser, the New Age is truly about to begin. She calls 2012 "a great opportunity, a very great opportunity ... for reunification. For all that is."
But plenty of others are taking no chances.
Florida developer Larry Hall showed us his plans for a decommissioned missile silo he recently bought out in Kansas. The silo is a 15-story luxury bunker, built to house 50 people indefinitely.
An Underground Noah's Ark
"2012 has a lot of people concerned," Hall explained. "And people are starting to realize that they need a plan B. And this Plan B beats everybody else's plan A, B and C."
It's a Noah's Ark for the paranoid man who has everything.
Each condo will be stocked with enough food to last five years.
The complex will also be outfitted with hydroponic agriculture... and treated water.
"Each level has a fireplace in it," said Hall. "You won't be laughing. These aren't Spartan finishings. These are high-end. There's even a fitness room and an indoor infinity pool."
Luxury on top of security doesn't come cheap.
"The full floors go for $1.75 million and the half-floors are $900,000," he said. "We've sold three."
All the sales were cash up front: Tough to justify a 30-year mortgage, when you're betting the bank the world's going to end in two.
"I don't take mortgages but the banks don't either," said Hall. "The people who are buying these are writing checks for them."
One person who won't be getting out his checkbook is Chris Powell.
His prediction for 2012: "The sun is going to rise and it's going to fall, and a lot of people are going to be watching it. ... I'm not worried and there's really no reason to be worried. There's no real prophecy that the world is going to end, not from the Maya, not from the ruins anyway.
"The Maya were basically positive people. What they were trying to divine in the process of time was how to work with it. I don't think they were afraid of it. I think they would have embraced it and done their best with it. Put our best foot forward, as we all should."