Every year, around the world, seasonal changes transform entire landscapes and draw in millions of creatures as these great events unfold. This fantastic series combines the epic scale of Planet Earth and the intimate, emotional stories of charismatic animals as they struggle to survive. Using state of the art technology, these programmes capture the Earth's most dramatic and epic wildlife spectacles and the intimate stories of the animals caught up in them.
The Great Melt: The summer melt of Arctic ice, opening up nearly three million square miles of ocean and land, provides opportunities for millions of animals, including beluga whales, families of Arctic foxes, vast colonies of seabirds, and the fabled Arctic unicorn, the narwhal. For polar bears, however, it is the toughest time of year. Why? How will they survive? A mother polar bear and her cub make their first journey together onto the sea ice. They are looking for ringed seals, their favourite prey. It is a serious business but the cub just wants to play. The melting ice makes it harder for them to hunt and threatens their survival. In a unique aerial sequence, the migration of narwhal with their distinctive unicorn-like tusks is filmed for the first time. The whales' journey is risky as they travel along giant cracks in the ice. If the ice were to close above them, they would drown. Hundreds of beluga whales gather in the river shallows. They rub themselves on smooth pebbles in one of the most bizarre summer spectacles. Guillemot chicks take their first flights from precipitous sea cliff nests to the sea 300 metres below. They attempt to glide to safety but many miss their target. Their loss is a bonus for the hungry Arctic fox family waiting below. As the melt comes to an end the bears gather, waiting for the sea to freeze again. Two 400kg males square up to each other to spar.

A mighty army of dolphins, sharks, whales, seals and gannets hunt down the billions of sardines along South Africa's east coast each winter. This is the Sardine Run: an underwater Armageddon, the greatest gathering of predators anywhere on the planet, and the most spectacular event in the world's oceans. From intimate moments of the creatures caught up in the run, to the dramatic finale of this spectacular event, The Great Tide is an action-packed feeding-frenzy, filmed underwater, on the ocean's surface, and in the air.
However, in recent years the sardine run has become less predictable, perhaps due to the warming effects of climate change. If the sardine run does not happen, the lives of the animals caught up in the drama hang in the balance. Pioneering a unique boat stabilised camera mount for surface filming, Nature's Great Events crew capture all the high octane action as the predators compete for sardines, filmed with aerial, underwater and above water cameras. Super slow motion cameras also capture the very moment gannets plunge into the water, hitting it at sixty miles an hour.
A violent winter storm is the trigger for the sardines to begin their desperate dash. They are followed by a super-pod of 5,000 dolphins and further up the coast more predators gather. A shoal of sardines 15 miles long is pushed into the shallows and aerial shots show thousands of sharks gathering to feed on them. The climax to the sardine run is a spectacular feeding frenzy as the dolphins round the sardines up into balls on which all the predators feast. Gannets rain down in their thousands, sharks pile in scattering the fish and a Bryde's whale lunges in taking great mouthfuls of sardines.

Experience up-close encounters with some of the most remarkable marine life ever captured on film while examining the impact of global climate change on the ocean wilderness as award-winning director/cinematographer Howard Hall travels from South Australia to the Indo-Pacific to teach viewers the importance of keeping our oceans clean for future generations.
Just how great of an effect does global warming have on marine wildlife, and what can be done to ensure the future well-being of our planet? As the filmmakers reveal the delicacy of our fragile ecosystem, viewers are allowed the unique opportunity to see what we risk losing should we fail to address the issue of global climate change sooner rather than later.

We are in the grip of an allergy epidemic. 50 years ago one in 30 were affected, but in Britain today it is closer to one in three. Why this should be is one of modern medicine's greatest puzzles. In search of answers, Horizon travels round the globe, from the remotest inhabited island to the polluted centres of California and the UK. We meet sufferers and the scientists who have dedicated their lives trying to answer the mystery of why we are becoming allergic to our world.

Does life exist on other planets? Astrobiology is a visionary new science that searches for life in space by combining the disciplines of astronomy, biology and geology. How did life evolve on Earth? What will life look like on other planets? These and other pertinent questions will be answered by a diverse group of scientists. Viewers will visit the Pilbara region of West Australia where the oldest evidence of life on Earth has been discovered. Travel to the moons of Jupiter and Saturn to test a theory that life could exist in the clouds of Venus. Finally, watch as experiments are done to see if life exists on exoplanets, earth-like planets beyond our solar system.

When man finally broke free of the Earth's gravitational pull the dream of travelling to other planets became a reality. Today scientists are proposing a bizarre array of technologies in the hope of travelling faster through space: from space craft sporting sails that catch laser beams, to propulsion engines powered by a bizarre entity known as anti-matter. Finally explore the science behind the seemingly fanciful notion of warp-drive and a theoretical particle that can travel faster than light.