Join National Geographic as they travel to the wilds of Africa to track the Nile crocodile, one of Earth's deadliest and most feared killers. The Nile crocodile is an ancient species-it has haunted Africa's waters since the age of dinosaurs. Yet in over 60 million years, this stealthy creature has changed little. A croc in its prime can reach 18 feet in length or longer, and weigh nearly a ton. It can lunge several feet in the blink of an eye and subdue prey as large as a buffalo. Once nearly decimated by hunters, these mighty giant crocodiles are making an amazing comeback. In a land where lions rule the savannah, Nile crocodiles are now reclaiming the rivers.

Golden Lion Tamarins

TBS National Geographic Explorer Show about Parakeets In the Wild and as Pets

In China, archaeologists unearth ancient mummies with European facial features, blond hair and blue eyes. Where did these Caucasians come? Four bodies, a scattering of clues, a mystery whose solution could rewrite history. National Geographic Explorer-in-Residence Spencer Wells, opens an ancient case of missing persons, using the latest advances in DNA technology to determine the origins of a group of enigmatic mummies found in western China. What he learns may change what we know about the world. The four individuals were part of a vanished world that existed in western China between 2600 and 4000 years ago - long before Marco Polo or the Silk Road. Yet these long-buried corpses look European and were found with tools that didn't exist yet in that part of the world. Who were they? Where did they come from? And how might they have affected the spread of culture and technology in prehistoric times?

Did Romanov Princess Anastasia survive a Bolshevik firing squad or did she and her brother Crown Prince Alexis perish with their father, Tsar Nicholas II, before another firing squad in 1918? The chance find of human remains in a Siberian forest brings forensic anthropologist Dr.Anthony Falsetti to in search of the truth. Marshalling DNA, ballistics and the very latest forensic analysis, an international team works to dispel the greatest myth of the 20th century and tell a real story more remarkable than any fiction.

The naval base at Guantanamo Bay secured a place in the annals of history when the first wave of detainees from America's War on Terror – men dubbed "the worst of the worst" – arrived in 2002. The goings-on inside the wire encircling this highly classified camp have been a closely held government secret — until now. National Geographic exclusively captures day-to-day life in the most famous prison in the world.

An extremely rare genetic disease passed down through generations, fatal familial insomnia's (FFI) primary symptom is sleeplessness, but with a fatal twist: victims are dead within months. National Geographic delves into the science of sleep to find out why we need sleep and what happens to us when we don't get it. Witness the pioneering research inside the sleeping brain as well as the mind forbidden to rest for days at a time.

Leonardo da Vinci's "The Battle of Anghiari" vanished 500 years ago, with only copies rendered by other artists left behind to confirm its existence. Scientist and art enthusiast Maurizio Seracini, has dedicated 36 years to tracking down the missing mural, and seems to be on the verge of uncovering the hidden fresco behind the walls of the Palazzo Vecchio in Florence, Italy.

National Geographic writer Neil Shea travels to the heart of Kurdistan on a quest to meet the Kurdish fighters on the front lines against the world's biggest terrorist threat, ISIS.

Giant Snakes. The serpents of our nightmares. Reaching more than 30 feet long and hiding in the swamps, the trees and the basement. Today's giant snakes are as big as they've ever been in their history, and they have the appetites to match. Search For The Supersnake dives into these reptilian marvels of engineering. Some 100 teeth, 300 vertebrae, 600 ribs, and 10,000 muscles work together to form one of nature's most elegant predators. But what are the limits of these enormous serpents? How big can they grow, constrict and consume? National Geographic debunks the internet tall tales while revealing startling truths about the seemingly limitless capacity of these totally tubular predators.

National Geographic celebrates the 25th anniversary of Explorer, the longest running documentary series in cable television history, with a commemorative special. Explorer has taken viewers to more than 120 countries, opening a window on hidden parts of the world, unlocking mysteries both ancient and modern, and investigating amazing and powerful stories of science, wildlife, and human nature. Hosted by Lisa Ling, the 25th anniversary special looks back at how the world has changed in a quarter century and how the award-winning Explorer series has chronicled our changing world. Highlights include Search for the Afghan Girl and Africa Extreme.