For the first time after seventeen years and their last appearance on the final episode of the TV series in 2004, Jennifer Aniston; Courteney Cox; Lisa Kudrow; Matt LeBlanc; Matthew Perry, and David Schwimmer, find themselves under the same roof for a reunion special. Hosted by James Corden, and produced by the show's co-creators, Marta Kauffman, David Crane, and Kevin Bright, the show's main cast feels at home in the original sets of Friends (1994), taking a trip down memory lane while sitting on Central Perk's couch.
Brimming with emotion, laughter, and tears of joy, 'Friends: The Reunion' sheds light on ambivalent endings, the casting process, and many more, as the main cast re-enacts older Friends episodes and meets with a plethora of celebrity guests, including Maggie Wheeler, the show's Janice Litman-Goralnik; Justin Bieber; Cindy Crawford; Cara Delevingne; Lady Gaga; David Beckham; Tom Selleck, and Nobel Peace Prize laureate, Malala Yousafzai.

For the animals in the polar regions, autumn means dramatic battles and epic journeys. Time is running out - the Arctic Ocean is freezing over and the sea ice is advancing at 2.5 miles per day around Antarctica. Polar bears gather in large numbers on the Arctic coast as they wait for the return of the ice. Soon, tempers fray and violent sparring contests break out. Meanwhile 2,000 beluga whales head for one special estuary, a gigantic 'whale spa' where they will thrash their snow-white bodies against the gravel and exfoliate. Inland, the tundra undergoes a dramatic transformation from green to fiery red. Here, musk ox males slam head-first into each other with the force of a 30mph car crash as they struggle to defend their harems. Frisky young caribou males play a game of 'grandma's footsteps' as they try to steal the boss's female. Down in Antarctica, Adelie penguin chicks huddle together in creches. When a parent returns from fishing, it leads its twins on a comical steeplechase - sadly there's only enough for one, so the winner gets the meal. Two months later and the chicks are fully feathered apart from downy Mohican hairdos - they're ready to take their first swim - reluctantly though, as it seems penguins are not born with a love of water! And with good reason - a leopard seal explodes from the sea and pulls one from an ice floe, a hunting manoeuvre that has never been filmed before. As winter approaches and everyone has left, the giant emperor penguin arrives and makes an epic trek inland to breed. The mothers soon return to the sea leaving the fathers to hold the eggs and endure the coldest winter on earth.

Our journey begins with David Attenborough at the North Pole, as the sun returns after six months of darkness. We follow a pair of courting polar bears, which reveal a surprisingly tender side. Next stop is the giant Greenland ice cap, where waterfalls plunge into the heart of the ice and a colossal iceberg carves into the sea. Humpback whales join the largest gathering of seabirds on earth to feast in rich Alaskan waters. Further south, the tree line marks the start of the Taiga forest, containing one third of all trees on earth. Here, 25 of the world's largest wolves take on formidable bison prey. At the other end of our planet, the Antarctic begins in the Southern Ocean where surfing penguins struggle to escape a hungry sea-lion and teams of orcas create giant waves to wash seals from ice floes -a filming first. Diving below the ice, we discover prehistoric giants, including terrifying sea spiders and woodlice the size of dinner plates. Above ground, crystal caverns ring the summit of Erebus, the most southerly volcano on earth. From here we retrace the routes of early explorers across the formidable Antarctic ice-cap - the largest expanse of ice on our planet. Finally, we rejoin David at the South Pole, exactly one hundred years after Amundsen then Scott were the first humans to stand there

Sir David Attenborough returns to the Galápagos Islands and travels throughout the archipelago to explain their origins and their unique fauna in evolutionary terms. He has captured a new species of pink iguana on film for the first time. In the first episode, the islands of the Galapagos rose explosively from the ocean four million years ago. Although life would not seem viable in such a remote Pacific outpost, the first arrivals landed as the fires still burned. David Attenborough explores the islands for the animals and plants that descend from these pioneers: from the sea birds carrying the seeds that made a tentative foothold on these rocks, to equator-dwelling penguins and a dancing bird with blue feet. This is a story of treacherous journeys, life-forms that forged unlikely companionships, and surviving against all odds. It is the story of an evolutionary melting pot in which anything and everything is possible.

One extraordinary family of fish has achieved the ultimate form of gender equality. When it comes to breeding, seahorses do it like no other animal on the planet. Their fierce females refuse to be left holding the baby. So it's the males that carry their brood. In this episode we explore the world of mating seahorses which are the only animals in the world that have a major gender role reversal.

George Harrison first became known to the world as 'The Quiet Beatle', but there was far more to his life than simply being a part of The Beatles. This film explores the life and career of this seminal musician, philanthropist, film producer and amateur race car driver who grew to make his own mark on the world. Through his music, archival footage and the memories of friends and family, Harrison's deep spirituality and humanity are explored in his singular life as he took on artistic challenges and important causes as only he could. Directed by Martin Scorsese.