Tonight's episode of DOOMSDAY PREPPERS, which airs on Nat Geo at 9pm ET, follows three New Yorkers who plot their routes out of the city so they can escape the grid to reach safety. Whether they're planning for a nuclear power plant meltdown or a dirty-bomb terrorist attack on NYC, these preppers have a plan for their journey to safety. But the third person, a woman who feared a catastrophic New York City hurricane -- even before Sandy hit the East Coast -- demonstrates how we need to plan for natural disasters and not just worry about the apocalypse.

In honor of tonight's episode, we want to help four people prepare for the next big disaster. We're giving away one DOOMSDAY PREPPERS T-Shirt and one "Complete Survival Manual" to each of the four recipients who correctly answer an easy quiz question about the series. But act fast -- you have to enter the giveaway before the Mayan Apocalypse on 12/21/12. If the world ends, you won't need the manual anyways, but if we all survive, you can use the guide to prepare for the next hurricane, earthquake or tornado.

About the DOOMSDAY PREPPERS Survival Manual & T-Shirt Giveaway

To enter the DOOMSDAY PREPPERS/TV Tango giveaway, you should scroll down and take an easy one-question quiz about DOOMSDAY PREPPERS. The FOUR PEOPLE who enter the giveaway before 11:59PM (Pacific Time) on Friday, December 21, 2012 and correctly answer the question each score the DOOMSDAY PREPPERS "Complete Survival Manual" and T-Shirt. If there is a tie and multiple people answer correctly, then four people from that group will be randomly selected to receive the giveaway. If the world ends on 12/21/12, the day the giveaway ends, then nobody receives the merchandise. The recipients must reside in the United States and be at least 18 years old.

The DOOMSDAY PREPPERS "Complete Survival Manual" features:

• 368 pages, with 300 color photos, 7 maps & 40 illustrations;

• "Prepper Profiles" of people in the show and survival tips from preppers themselves;

• how-to illustrations to help prepare for the most devastating calamities;

Enter the DOOMSDAY PREPPERS Survival Manual & T-Shirt Giveaway

At the beginning of the quiz, we do ask that you enter your email address and name (as User Name) so we can contact you if you're selected. TV Tango respects your privacy and will not sell, distribute or otherwise use your email address for any purpose other than to possibly communicate directly with you for this giveaway.

Update at 12:05am PST on December 22, 2012: Since the world didn't end, we're going through all of the entries and will randomly select four lucky recipients.