Most big cats do their best to remain hidden from human eyes, but none are quite as adept at this as the snow leopard. These cats lead largely solitary lives, populating the Himalayas at altitudes that offer only about half the oxygen to which humans are accustomed. So when wildlife filmmakers Hugh Miles and Mitchell Kelly set out to film this animal they knew they were in for a challenge.

Every dark element of a mighty human empire building has long been perfected by the insect world. In NGC's Insect Wars, the violent existences of insect empires are explored and the sometimes brutal battlefield tactics, ingenious defensive strategies and struggles for power between empires are revealed. Go into the inner sanctums of the world's mightiest insect empires and catch a rare and close-up glimpse at the world of invertebrate power not often seen by the naked eye.

There’s a jungle inside Vietnam’s mammoth cavern. A skyscraper could fit too.

Hear author Mark Jenkins and National Geographic’s Boyd Matson talk about what could be considered the largest cave in the world, the 2.5-mile Hang Son Doong, or mountain river cave, along the Vietnam-Laos border.

Is it the World’s Biggest Cave? More than three times the height of Niagara Falls, much of Vietnam’s Mountain River Cave has remained untouched by humans until now.

Orange-and-black wings fill the sky as NOVA charts one of nature’s most remarkable phenomena: the epic migration of monarch butterflies across North America. NOVA’s filmmakers followed monarchs on the wing throughout their extraordinary odyssey.

To capture a butterfly’s point of view, camera operators used a helicopter, ultralight, and hot-air balloon for aerial views along the butterflies’ transcontinental route.

The beauty of America’s Yellowstone National Park masks one of the rarest and most destructive forces on Earth – a supervolcano. A two-part BBC factual drama asked: What if Yellowstone erupted?

Amidst the stunning wilderness of America’s most famous National Park, steam and hot water bubble and hiss from thousands of colorful, mineral-encrusted springs and vents. Together with its wildlife and spectacular scenery, these geothermal phenomena make Yellowstone one of the most incredible places on the planet.

Discover the unique cultures, places, landscapes and critters that make Madagascar one of the most marvelous places on earth!

Aussie Adventurer and Award-winning Newsman, Greg Graingers passion for exciting destinations has led him to film activities as diverse as sky burials in Tibet to Shark riding in Tahiti.

His films are fast-paced and exciting, offering viewers a dynamic experience that will keep them on the edge of their seats!