For thousands of years, mankind has found comfort in its presence. It's been a lantern for nighttime travellers, a timekeeper for farmers and a location finder for sailors at sea. For some cultures, it's even been a god. It's the only cosmic body ever visited by human beings. From afar, the Moon's luminance has captivated us since the beginning of time. And a closer look at the beacon in the dark sky reveals an ever-present source of myth, intrigue, controversy and unsolved mysteries. The field of science may cast an empirical light on some things about the Universe, but lunar experts are the first to admit they don't have all the answers when it comes to our Moon. This episode explores the theories behind Lunar Transient Phenomena that have left scientists stumped for centuries; takes to the Canadian waters to see how the Moon effects our planet through tides; and dusts off some age-old myths and weighs arguments that without our Moon, humanity may not even exist.

The big blue is the world's greatest wilderness, far from shore and many kilometres deep. It's a vast marine desert where there is little to eat and nowhere to hide. Yet it's home to some of the biggest and most spectacular creatures on earth. This episode reveals what it takes to survive in this savage and forbidding world. We witness feats of incredible endurance, moments of high drama and extraordinary acts of heart-wrenching self-sacrifice. Every animal in the big blue must find their own unique way to survive. Sperm whales have the largest brains in the world. They live for 80 years, and we are only now beginning to learn the extraordinary complexity of their language of clicks - thought to coordinate the whole family in everything from childcare to hunting. With special pressure-proof cameras, we witness record-breaking feats of endurance as they hunt for squid a kilometre down into the abyss. Only recently have we begun to solve the mystery of where baby turtles disappear to in their early years. They leave the crowded waters of the coast and head to the open ocean, where they use floating debris like logs as life rafts. Here they remain until adulthood, adrift on the high seas in relative safety away from coastal predators. Over half of all animals in the open ocean drift in currents. Jellyfish cross entire oceans feeding on whatever happens to tangle with their tentacles. The jelly-like Portuguese man-of-war can harness sail power to fish with its deadly tentacles. Sometimes there is a brief explosion of food in this marine desert, but ocean hunters must be fast to make the best of this bonanza. We witness super pods of up to 5,000 spinner dolphins racing to herd vast shoals of lanternfish, briefly caught at the surface where it is thought they spawn. New aerial footage reveals, for the first time, the truth to a centuries-old sailors' legend of the 'boiling seas' - the spectacular feeding frenzy of 90kg tuna and dolphins smashing through the lantern fish shoals turning the sea white with foam.

Recent archaeological sites in England offer a whole new perspective on the life and death of the seafarers and marines who built the British Empire in the 18th and 19th centuries. The bones of sailors reveal surprising and shocking facts. Apparently not only seasoned men but also half children did their service in the Royal Navy; according to the investigations, the youngest were no older than 13 years. A forensic archaeologist studies the injuries on bones discovered at the site of an battle and suggests how these people may have died.
Three-hundred-and-fifty skeletons, exhumed from Royal Navy graveyards from the age of Nelson's Navy, are throwing an extraordinary new light on how these sailors lived, fought, outwitted their enemy, and, from the oldest to youngest, suffered for victory. These men were the beating heart of the most victorious fleet in history and never have so many of these sailors' remains been available for forensic investigation.
Six remarkable stories stand out: the child sailor, the top man, the American gunner, the freed slave, the marine and the victim of the sailor's most dreaded disease: syphilis. Broken bones, amputations, injuries from blows with a saber or cutlass, sexually transmitted diseases, but also malnutrition - the list of causes of death is long. There is definitely no tale of seafaring romance. These fighters and sailors sailed the globe as cannon fodder, conquered an empire for the crown, and were themselves forgotten. No longer just bones in a box, the men of Nelson's Navy are back from the dead.