The octopus is the closest we may get to meeting an alien. They evolved from a common cousin more than 500 million years ago, but are also intelligent creatures with proven problem-solving abilities. So what happens when you invite an eight-legged alien into your living room? This documentary follows marine biologist David Scheel as he tracks his evolving relationship with his own octopus.

Academy Award-winning Passion Pictures and HHMI Tangled Bank Studios present one of the most important, but untold, science stories of our time—a tale with profound implications for the fate of life on our planet. Beginning in the 1960s, a small band of young scientists headed out into the wilderness, driven by an insatiable curiosity about how nature works. Immersed in some of the most remote and spectacular places on Earth—from the majestic Serengeti to the Amazon jungle; from the Arctic Ocean to Pacific tide pools—they discovered a single set of rules that govern all life. Now in the twilight of their eminent careers, these five unsung heroes of modern ecology—Bob Paine, Jim Estes, Mary Power, Tony Sinclair, and John Terborgh—share the stories of their adventures, and how their pioneering work flipped our view of nature on its head. Across the globe, they discovered that among the millions of species on our planet, some are far more important than others. They called these species “keystones” because they hold communities of plants and animals together, just like a keystone holds a stone arch in place. When keystones are removed, ecosystems unravel and collapse—a phenomenon no one had imagined or understood until their revolutionary discoveries. But with new knowledge also comes new hope, and these same visionaries reveal the remarkable resilience of nature—and how the rules they discovered can be used to restore the natural world, from American lakes to war-ravaged African parks.

In Ecuador’s Amazon basin lies a special patch of jungle that is a living, breathing, green metropolis of life. It is an untouched, secluded wilderness teeming with biodiversity, only accessible by boat. Follow a team of naturalists and filmmakers on a mission to capture the intimate behaviors of the wildlife who dwell here by installing a network of more than 50 remotely operated cameras and mini-cams, from the dark rainforest floor right up to a tangled canopy 300 feet in the air. By filming 24/7 for an entire month, the camera crew captures the lives of exotic creatures and discovers the incredible tricks these animals use to survive in the extreme jungle climate. From agile pygmy marmosets and boisterous howler monkeys, to solitary pumas and mesmerizing leaf-cutter ants, meet a cast of remarkable animal characters carving out a living in this tropical world.

Paradise presents the landscape and wildlife of the Upper Okavango River. A lioness severely injured by a buffalo is left for dead by her pride. Now handicapped, she has to survive in the swamp alone, hunting to feed her little cubs.

Limbo presents the landscape and wildlife of the "Middle World," the delta of the Okavango River. A hyena and a warthog family share neighboring dens, helping each other by keeping an eye on threatening predators such as lions and leopards.

Inferno presents the landscape and wildlife of the Lower Okavango River. The landscape is baked dry by the scorching sun, and large herds of zebra and wildebeest migrate to the dry plains in search of precious salt that these animals need.

Discover the ingenious strategies that nature’s biggest beasts employ to conquer their environments, from the Komodo dragon with a deadly bite to the tallest giraffe to the bird-eating Armored ground cricket. These are their epic survival stories.

Discover the ingenious strategies that nature’s biggest beasts employ to conquer their environments, from the Komodo dragon with a deadly bite to the tallest giraffe to the bird-eating Armored ground cricket. These are their epic survival stories.

Follow the adventures of bears across the globe, from grizzlies to pandas to sloth bears, as they draw on their brains, brawn and unique adaptations to survive. Find out what it really takes to be a bear in today’s ever-changing world.

A filmmaker investigates his traumatic encounter with a 30-ton humpback whale that breached and almost landed on him while he was kayaking. What he discovers raises far bigger questions about humans’ relationship with whales and their future.

Go beneath the surface and meet Africa’s river giants, the hippos. Discover an unexpected side of these aquatic mammals that can’t even swim as hippos protect their families, face their enemies and suffer in a drought. Narrated by David Attenborough.

Florida is home to beaches, coral reefs, pine forests and the famous Everglades wetland, but a growing human population and abandoned exotic pets like pythons are threatening this wild paradise. Can Florida’s ecosystems continue to weather the storm?

Discover the truth about the infamous weasel, often associated with unsavory behavior. Do these critters deserve their bad reputation? Follow the adventures of a first-time weasel mom, fearless honey badger and a tiny orphan weasel

In the crystal-clear waters of the Caribbean, Cuba is an island teeming with exotic biodiversity: from coral reefs pulsating with life to five-foot-long Cuban rock iguanas. As international relations thaw, what will become of this wildlife sanctuary?

There are more than 100 domestic and wild kinds of rabbits and hares, from snowshoe hares to Flemish giants. Despite their remarkable ability to reproduce, many wild rabbits are in danger of being eradicated.

The spy creatures investigate the wildlife that thrives in the tropics. They infiltrate a hippo pod, a nursery of red flying foxes, a gorilla sanctuary and the secret world of pygmy forest elephants.

Travel to the Northern Hemisphere, where the spy creatures learn how animals move, feed and fight. A spy hummingbird films millions of butterflies, and a spy squirrel winds up in a battle. A spy beaver observes other beavers building dams.

Explore the islands of the South Pacific with creatures like the spy koala, who captures breeding behavior in Australia, or the spy crab, who joins an army of red crabs on their march to the sea to deposit their eggs.

From penguin chicks to elephant seals and wolf cubs to polar bears, the spy creatures meet and observe the hardiest and most charismatic animals in the Arctic and Antarctic circles.