of l.A., They're busy building for doomsday. This is it, huh? This is it. Reporter: This is the atlas survival shelter, the ultimate man cave. Only, it doesn't go anywhere. It's built to be buried... See More
of l.A., They're busy building for doomsday. This is it, huh? This is it. Reporter: This is the atlas survival shelter, the ultimate man cave. Only, it doesn't go anywhere. It's built to be buried deep under ground. How many of these things are you selling? Last year, it was one a month. Then, it went to one a week. Then, since december, it went to one a day. Reporter: This is one of a growing number of companies catering to catastrophe. This is going to protect us against nuclear, biological, chemical attacks, tornadoes. Reporter: It's definitely helped business in a an ancient mayan prophecy predicts this friday may mark some sort of global exploration date. It appears on december 21st of 2012. And he descends. And he performs a ritual. Reporter: Lots of people are now projecting modern anxieties on to that ancient mayan date. That the financial system might collapse. Or that global warming. Or solar flares. Or an act of terrorism might take out the nation's electrical grid. People are worried that what's left might look a lot like the recent movie "the road." How many people do you think are still alive? In the world? Not many. Reporter: Doomsday prepping is such a fad, there's popular reality shows based on it. MANY 2012ers ARE NOT SO NEGATIVE About the mayan prophecy. We met a woman who will be at the ruins thursday, praying to her crystal skull. She believes this will mark the dawn of a new, more enlightened age. Others, not so much. I'll be in my shelter in texas. Just in case. Reporter: Just in case? Just in case. I'll feel really silly that i put a shelter underground and i WASN'T IN IT COME DECEMBER 21st. Reporter: After that, he plans to come back to l.A. To build more. David wright, abc news, montebello, california. I like that idea, that it's the dawn of a new, enlightened age. I think it's going to be the day before friday. Coming up, "magic mike" star, channing tatum, working
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