Some mysteries elude reason and avoid explanation. But they can't escape science. Starting December 4th, the world's most captivating mysteries go up against the most advanced science. The journey begins by reconstructing history. Experience Stonehenge as it was 4,000 years ago on the premiere of Rebuilding Stonehenge. As three days of mysterious science begins Sunday, December 4th at 9 on the National Geographic Channel. Dare to explore. Dare to explore the National Geographic Channel. Let's face it, there are a lot of bad drivers out there. You can't change their driving, but you can learn to avoid them. That's why at Liberty Mutual, we teach something called decision driving. And offer the latest auto safety advice. To keep the road safer and keep premiums down. Liberty Mutual, it's more than insurance, it's insurance in action. Looks like we've got some work to do. This month I will rack up a NASA cell phone bill talking about absolutely nothing. When my parents open next month's cell phone bill, they will cry. My calls will be monitored like a felon. My dad's patience with my cell phone bill will run out at a socially crippling time. Don't get schooled in wireless. Get GoPhone. Pay as you go with cash or pick your plan with debit or credit. GoPhone comes with everything but a surprise bill. I will be grounded several times this year, but not because of my GoPhone. Only from Singular, raising the bar. Only Cancun is for everyone. Having everything for your vacations. Calm blue waters that caress golden beaches. Majestic Maya culture, closely overseen by natural wonders that weave a spectacular backdrop for ecotourism. And some of the best golf courses in the world. Or how about pampering yourself in marvelous spots? Relaxing in superb shopping locations. Breathing the romance that fills the air and sets the ideal stage for a wedding or a honeymoon. Everything ever embraced by Mexican hospitality. Come and discover firsthand why Cancun has it all. Cancun. Only in Mexico. Mexico. Beyond your expectations. Somewhere, someone understands what a millimeter really means. Someone understands the difference even a single millimeter can make in the way a car looks, drives, and feels. Someone as obsessive about quality as we are. We know you're out there. Somewhere. And we just wanted you to know, you're not alone. Introducing the all-new View of Lucerne. Beyond precision. Look for this exciting issue of National Geographic Magazine on newsstands. Or call the number on your screen to subscribe. In a showdown with Shep. Grand Central Terminal. 750,000 people travel through it every day, but few know its secrets. Beyond the brick and mortar lies a city within a city. Go deeper, below the surface. Inside hidden tunnels, mysterious elevators, and secret railways. Go inside Grand Central. Premieres December 8th at 8 on the National Geographic Journal. Dare to explore. Witness a transformation. Sony SXRD technology delivers 2 million pixels of red, green, and blue. Twice the pixels of HD as we know it. But that's what makes the new Grand Vega SXRD a Sony. The world's greatest high-definition television. Make it yours at sony.com slash HDTV. Like no other, Sony. When you have a pet, life is better. Because pets enrich our lives in immeasurable ways. Purina shares your passion for pets. It's why we continue to do all we can to help pet owners make the world a better place for pets. Purina, your pet, our passion. Discover unique ways to enrich your pet's life at purina.com. Technology has made your morning easier. Why not your shave? The new Philips Norelco Smart Touch XL is designed to shave more with every touch. With three shaving rings in each shaving head. And because now it pivots to stay on your face and neck, even tricky hairs are cut. Make every stroke count. Philips Norelco. Let's see, we got Vonage a couple of months ago. It was easy to install. I mean, I'm not really technical at all, and I did it myself. Look, I just used our old phone. And it cost less, too. It's just $24.99 a month, and that includes voicemail, call waiting, caller ID, and a lot more at no extra charge. So we just love it. We're not out to change the world. Just the way you talk to it. Sign up now and get your first month free. Call 1-800-930-4B-ON. High-speed Internet connection required. Sunday. Bodies are discovered in a mass grave. How does this one crime scene relate to the disappearance of an entire civilization? Last Days of the Maya, world premiere on Explorer, Sunday at 8 on the National Geographic Channel. America's favorite home gym is more affordable than ever. Now you can get the all-new Bowflex Extreme for just $19 a month. Call the number on your screen for a free DVD or video and check it out. Bowflex's Power Rod technology delivers results. Powerful arms, defined legs, a stronger chest, and a toned, sexy core. And owning a Bowflex home gym is so affordable. Great results are easy with a new Extreme. All it takes is one simple workout, 20 minutes a day, three times a week, to get in the best shape of your life. The Extreme is built so well that we back it with an unrivaled seven-year warranty. And so effective, it comes with Bowflex's 100% satisfaction guarantee. Through this special offer, you can own one with no money down and just $19 per month. You can't get this Bowflex deal anywhere else. Call us for a free DVD or video or visit us online and find out how to get your Bowflex for just $19 a month today. Sunday on Explorer, when bodies are discovered in a mass grave. This was caught by a heavy, sharp instrument. This one was hacked. Explore unearthed shocking evidence that leads to one of the greatest unsolved cases of the ancient world. Real hardcore evidence of the Maya collapse. How does this one crime scene relate to the disappearance of an entire civilization? Last Days of the Maya, world premiere on Explorer, Sunday at 8 on the National Geographic Channel. Dare to explore hidden tunnels, mysterious elevators, secret railways. Go inside Grand Central. Premiers December 8th at 8 on the National Geographic Channel. Now tomorrow, your dad is picking you up from... Tennis practice. Right, tennis. And then on Tuesday? Band. Okay, and Thursday and Friday? Voice lessons. Right. And then on Saturday? I'm going to the mall. To the movies with your mother and father. Mom? I love you too, baby. Love is getting your children involved in positive activities to help keep marijuana out of their hands and out of their lives. When you have a pet, life is better. Because pets enrich our lives in measurable ways. Purina shares your passion for pets. It's why we continue to do all we can to help pet owners make the world a better place for pets. Purina, your pet, our passion. Discover unique ways to enrich your pet's life at purina.com. Ordinary toothbrushes can't stand up to it. New Oral-B Triumph. Triumph is the first brush with an onboard computer to help you brush better. And a Floss Action Brush Head to power clean deep between teeth. That means dramatically cleaner teeth and healthier gums. Get a smile you can feel triumphant about. New Oral-B Triumph. Brush like a dentist. I'm thinking of a number between 450 and 850. Do you know what it is? It's my credit score. And it happens to be 720. The higher my credit score, the better chance I have of saving a lot of money. Do you know your credit score? Do you know what's in your credit report? You can find out right now at freecreditreport.com. You can even print it out if you want to. How much easier could it get? Log on to freecreditreport.com. That's freecreditreport.com. Offer applies with enrollment and triple advantage. Systems with Intel Pentium 4 processors with HD technology and a 19-inch flat panel start at $949. XPS, the ultimate Dell PC. A new original genre in television. News with passion. This is where the story is. Out with the people. To roll through at lunch every weekday. Check your local listings. X marks a daring pursuit of the unknown. X marks questions that need to be explored. Stories that need to be told. X marks the destination for unforgettable adventures. X marks Explorer. Sundays at 8 only on the National Geographic Channel. Brought to you by Nissan, who reminds you to shift the way you move through the world. Only Cancun is for everyone. Having everything for your vacations. Calm blue waters that caress golden beaches. Majestic Maya culture closely overseen by natural wonders that weave a spectacular backdrop for ecotourism. And some of the best golf courses in the world. Or how about pampering yourself in marvelous spots. Relaxing in superb shopping locations. Breathing the romance that fills the air and sets the ideal stage for a wedding or a honeymoon. Everything ever embraced by Mexican hospitality. Come and discover firsthand why Cancun has it all. Cancun. Only in Mexico. Mexico. Beyond your expectations. Witness a transformation. Sony SXRD technology delivers 2 million pixels of red, green and blue. Twice the pixels of HD as we know it. But that's what makes the new Grand Vega SXRD a Sony. The world's greatest high definition television. Make it yours at Sony.com slash HDTV. Like no other, Sony. When you have a pet, life is better. Because pets enrich our lives in measurable ways. Purina shares your passion for pets. And we continue to do all we can to help pet owners make the world a better place for pets. Purina. Your pet. Our passion. Discover unique ways to enrich your pet's life at Purina.com. Sunday. Bodies are discovered in a mass grave. How does this one crime scene relate to the disappearance of an entire civilization? Last Days of the Maya. World premiere on Explorer. Sunday at 8 on the National Geographic Channel. America's favorite home gym is more affordable than ever. Now you can get the all-new Boflex Xtreme for just $19 a month. Call the number on your screen for a free DVD or video and check it out. Boflex's Power Rob technology delivers results. Powerful arms, defined legs, a stronger chest and a toned, sexy core. And owning a Boflex home gym is so affordable. Great results are easy with a new Xtreme. All it takes is one simple workout, 20 minutes a day, three times a week, to get in the best shape of your life. The Xtreme is built so well that we back it with an unrivaled seven-year warranty. And so effective, it comes with Boflex's 100% satisfaction guarantee. Own the Xtreme with no money down and payments of just $19 a month. And when you call right now, we'll give you the leg attachment upgrade free. Call for a free DVD or order your Boflex Xtreme for only $19 a month. And for a limited time, get the leg attachment free.