Some preppers believe in safety in numbers -- as is the case for Jeff Mann, who leads "the Colony," a community of 25 preppers unified with the single purpose of surviving doomsday. Watch as he prepares his son, Colten, to take the reins by having him hunt down live boar in the Florida swamps and builds the Colony's very own gallows -- an important message that there are laws to be upheld, even in times of chaos.

An economic collapse could mean total chaos for the U.S. -- looting, riots and civil unrest are top concerns. In Washington state, Steve works with a stern hand to prep his family for the potential threat. South Carolinian David Appleton is a comedian, but the idea of a devastating earthquake is no joke to him. His job doesn't always pay the bills, so David must Dumpster dive to find supplies to make a DIY camouflage net to hide his preps.

Could an explosion on the surface of the sun cause mayhem on Earth? Jason and Jacob are a father-son team from Alabama who are prepping for exactly that: a global solar flare with the potential to wipe out power grids around the world. Jason was almost stranded for good in the wilderness when he was 19, but that will not stop him from prepping in those very same woods by molding his own ammunition and preparing his 20-piece bug-out pack.

The possibility of World War III is a major concern for many preppers, including former Marine Alex Dunbar, who is training a private army of German Shepherd attack dogs in San Luis, Colorado. In the woods of East Appalachia, Brenda McSwigan fears that a vicious mutating virus will lead to a pandemic that will overwhelm hospitals and leave the rest of the country in chaos. Another prepper, Grace McLeod, secures her 3,500 square-foot fortress before an economic collapse.

Deep in Oregon's backcountry sits an 80-acre off-the-grid estate that prepper Curt and his family have designed as a fortress in the event of an economic collapse. Isolation is one of their greatest strengths, but the protective measures are endless: a 3,000-square-foot greenhouse, a lake with 1 million gallons of water, infrared cameras and a high-tech software system — not to mention the children are trained in marksmanship.

Prepper Chad believes that a nuclear strike resulting in a genocidal siege is a real possibility. At his home in Arizona, he is working on executing the biggest prep of his life — a 140-foot-long escape tunnel from his family's house to a bug-out vehicle. With the help of his wife and daughter, he begins construction — but as the project unfolds, they realize they're in over their heads.

While many preppers believe defense is the best strategy for surviving a Doomsday scenario, one family in Tacoma, Wash., is banking on a good offense. Tyler, his wife and his cousin have assembled a group of like-minded, would-be marauders from their neighborhood in preparation for a catastrophic domestic terrorist attack. They have only six months' worth of food because they plan on taking what they need in order to survive — and to stay safe, they're developing the ultimate suit of armor.

A devastating EF-5 tornado, like the one that struck Oklahoma in May of this year, can throw buildings into the air and hurt hundreds of people. In Tennessee, Tracy is preparing for just that. Tracy has spent six years prepping his farm for a super tornado, but if it does hit, he doesn't plan on hunkering down — he plans on gathering his family and making a getaway in his mobile safe room.

To protect his family from Doomsday marauders, Rob is devising the ultimate booby-trap system. He's securing his Texas property's perimeter with an elaborate system of alarms, traps and defense mechanisms. In Tenn., Greg is preparing for a financial catastrophe by building an invisible tree house where he hopes to be safe from looters. If the build goes as planned, his family will have a tree house 12 feet into the forest canopy, with mirrored paneling and a stockpile of food, water and ammo.

Meet two families who both fear the end of the world is fast approaching. In Texas, John Tucker and his family are preparing for Category 5 hurricanes that they believe will change the landscape forever. After living in a home that was split in two during a hurricane, John vowed he would never again be unprepared. And in Utah, brothers Bret and Shane are preparing for a complete economic collapse. To protect their families, they are building a sniper post complete with the ultimate sniper rifle.

In Texas, Kenny and his wife Connie are preparing for a civil war. With defense as their ultimate concern, they're building a fortified bulletproof rooftop command center. In Maryland, Kevin is prepping for an EMP attack. Kevin is very protective of his close-knit family, including his three pregnant daughters. Their survival plan relies on a customized 15-ton bunker buried 20 feet underground and stocked with baby supplies and doomsday essentials

Outside of Fort Worth, Texas, Vietnam veteran Richard Huggins is preparing for a nuclear strike by a terrorist state, a concern he believes is amplified by his proximity to the defense production hub of Dallas-Fort Worth. Meanwhile, in rural Colorado, Dr. Dave, his wife, Dee, and their young daughter are prepping for a possible solar flare that could lead to widespread illness and death due to lack of medical care.

Meet two Tennessee families who are both preparing for an earthquake in the New Madrid Seismic Zone. David Mays believes all roads and bridges leading out of his neighborhood will be destroyed, so he's devising the ultimate Doomsday drone fleet. Meanwhile, 100 miles away, do-it-yourselfer David Nash is building a geodesic dome -- considered one of the most stable structures on earth as it eliminates the need for load-bearing walls -- that will house his family during the earthquake's aftermath.

n Georgia, Mark believes that the U.S. is under the threat of foreign occupation, specifically by Russia. He's building a modern Trojan horse in order to infiltrate a potential enemy base undetected. In Texas, Joe is preparing for a cyberattack to take out the country's telecommunications system. His current projects include a post-apocalyptic schoolhouse to be used to educate children if the government collapses after disaster and "gyro-copter" in order to maintain aerial dominance.

Meet Jimi Falcon, who is prepping for a potential World War III. Jimi built his home to withstand the extreme climate of Montana. Next, meet Cindy Stewart, who began prepping for a foreign nuclear attack on the U.S. following the Sept. 11 terrorist attacks. Cindy uses her taxidermy skills to create camouflaged IEDs. Lastly, get a close-up look inside Rod Godfrey's military-style command and control center he built in his home to protect himself from apocalyptic superstorms.

After losing his job, Nick Klein began prepping for an economic collapse. Nick keeps rabbits that he believes will give him all the food, fuel and fertilizer he needs to survive. Patrick Troy began prepping for societal collapse caused by a catastrophic event after the birth of his only child. He is building a multi-tiered perimeter defense system around his house. Keith Ford is prepping for a second civil war that he believes will destroy American society.

Roger Dougan lost his home in a fire seven years ago. He's working to become self-sufficient through prepping, so he never has to feel helpless again. Before the 2000 New Year, Curtis bought a generator and stocked up on food and water, but it occurred to him that if something serious did happen, he wasn't nearly as prepared as he should be — so he became a prepper. Karissa Baca lost her job during the 2008 financial crisis, causing her to realize how fragile the economy is and begin prepping.

Chuck Vessey fears that an electromagnetic pulse will take out the power grid near his Texas home. He's concealing his goods in intricate spots around his house and building a wind turbine to generate electricity. Lisa Roulette preps for global climate change and teaches her sons the ways of living off the land. Tom and Beth Tailer prepare their land and community in rural Vermont for massive oil shortages by engineering a seemingly indestructible eco-dome shelter.

On their 53-acre property, Jane and Rick Austin prepare for an electromagnetic pulse disaster by disguising a greenhouse, food forest and gray water recycling system in what appears to be overgrown underbrush. Jim Lebus is prepping for an earthquake that he fears will paralyze the West Coast. In Virginia, a band of teenage boys, led by 16-year-old Jack Houston, join forces to test their wilderness survival skills.

Jerry McMullin, a retired risk assessment analyst, has put millions of dollars into his safe house. In case of a biological attack, Jerry has built an ultraviolet radiation chamber intended to disinfect the contaminated population, and will use solar panels and wind turbines to sustain power inside the safe house. The Jackling family will do everything in their power to protect their home and family from a wildfire they fear will ravage their Californian community.

Bruce Beach a lifelong prepper is focused upon nuclear wars and saving children in his 42 underground buses; Jeremy and Kelly, are concerned parents in Salt Lake City, preparing for the collapse of society due to peak oil depletion; Bradford Frank of San Diego, California works around the clock in case of a worldwide pandemic that will end life as we know it.

John Major has gone to the extent of moving his family to Idaho for a better more natural lifestyle; Janet Spencer an author in Montana decided because of her location to prepare for any "unnatural" event; Jack & Jackie Jobe, although new to prepping have done quite well for their future survival.

Barry, Pink and Cole have the ultimate urban underground foxhole right in the garage. Hooray! one if the best we have seen; Steve Pace a hometown survivalists is ready to take on long term electric failure; Carolina resident Laura Kunzie has concerns to a rapid airborne flu outbreak and is preparing so.

Texas prepper "Dr Wayne" bases his doomsday fears on a Chinese financial takeover and he has prepared many ways to survive these events; John & Cristina Sellers, are both hardworking Americans who want to protect what they have; Jason & Tanya have done their homework on how life and prepping can happen on a budget.

Martin Colvill lives on the road with his wife as a "survival trucker" and looks to prepare for the upcoming economic collapse; Donna Nash is prepared to quarantine all her family members to protect against a global pandemic; Kevin O'Brien is concerned about losing his home due to rising sea levels created by global warming or a polar shift.