It's long been known that German soldiers used methamphetamine called Pervitin in the Second World War. But have tales of Nazis on speed obscured the other side of the story: the massive use of stimulants by British and American troops? Did total war unleash the world's first pharmacological arms race? Historian James Holland quests to dig deeper and unearth the truth behind the war.

Lots of ground pounding, dirt-flying, close-up action with sing-s-long songs and trucks of every shape, size and kind! Contains more trucks than any other video of its kind! Spectacular camera shots and lots of real-life sounds make this a big favorite.

Vipers have been evolving their way to the top of the reptile heap for millions of years. See how these traits are working in an ever-changing world where skills new and old are constantly put to the test.

Pete Nelson builds with his head in the clouds "quite literally" as he brings to reality the fantastical treehouse imaginings of his clients. But you'll soon see that these treehouses are much more than child's play.

Here they come, toot-tootin' on down the track with lots and lots of toy train fun for everyone in Volume 2. Filled with the biggest and best nonstop model railroad action you'll find anywhere. Everyone will want to dance and sing along to The Alphabet Train Song; I've Been Working on the Railroad; The Magical Christmas Train; The Little Red Caboose; Train Stamps; and many other favorites. You'll be amazed by the colorful toy trains of every shape...

Sometimes the messiest stuff and the biggest mistakes can take you someplace wonderful. With the help of their hit TV show, Fixer Upper, the husband and wife team of Chip and Joanna Gaines have transformed the seemingly everyday work of renovating homes and flipping houses in Waco, Texas, into something much more. With their fun personalities, good humor, strong love of family, and unique design style, they've managed to capture the hearts of Americans...

Alzheimer's disease ravages the minds of over 40 million victims worldwide. The cause of Alzheimer's and whether it can be stopped is one of the greatest medical mysteries of our time. Join courageous patients participating in clinical trials, and then go behind the scenes of the major drug trials to see how researchers target and test therapies that may slow and even prevent Alzheimer's.

Investigates the science behind the dangers of a high-altitude electromagnetic pulse (HEMP).

The daughter of Keikobad, ruler of the spirit world, has married an Emperor. As a result she is now neither human nor a spirit and cannot bear children unless she can find a shadow.

Journey to Africa's Congo River basin as National Geographic embarks on a treacherous expedition to find out what powerful environmental forces created the tiger fish and to reveal the array of fantastic creatures that also inhabit this underwater Eden.