On the coast, two worlds collide. Coasts are the most dynamic and challenging habitats in the ocean - that brings great rewards but also great danger. The extraordinary animals that live here must find ingenious ways to cope with two very different worlds. This episode is a rollercoaster ride of heart-stopping action and epic drama, peopled with characters from the beautiful to the bizarre. We meet fish that live on dry land and puffins that must travel 60 miles or more for a single meal, and witness a life-and-death struggle in a technicolour rock pool. In a secluded cove in the Galapagos, sea lions feast on 60kg tuna. It should be impossible - tuna are usually far too fast for sea lions to catch. But here the sea lions club together to herd their prey inshore. Once trapped in the shallows, these huge fish are easy pickings. As the tide recedes in Brazil, lightfoot crabs leap from rock to rock, desperately avoiding the water - their lives depend on it. Moray eels launch themselves from rock pools, jaw gaping. Then octopuses, too. Both crawl across dry rock to set their ambush. Elsewhere, the ever-changing tides create rock pools. But these temporary worlds are a battleground. Predatory starfish turn a magical garden into the stuff of nightmares.

The deep is perhaps the most hostile environment on earth, at least to us - a world of crushing pressure, brutal cold and utter darkness. We have barely begun to explore it, and yet it is the largest living space on the planet. Scientists already think that there is more life in the deep than anywhere else on earth. This episode takes us on an epic journey into the unknown, a realm that feels almost like science fiction. We discover alien worlds, bizarre creatures and extraordinary new behaviours never seen before. We encounter savage hordes of Humboldt squid hunting lanternfish in the depths and coral gardens flourishing in absolute darkness, with more species of coral to be found in the deep than on shallow tropical reefs. Narrated by David Attenborough.

Bladderwort utricularia is a pond-dweller that is among the fastest known, its traps snapping shut in less than a millisecond. As the seasons change, David demonstrates how plants operate on a different time scale to us; how they modify their lives according to the time of year. We discover insects’ hidden links with plants, both as pests and pollinators. UV-sensitive 3D cameras reveal the invisible alter-ego of plants and their flowers’ mesmerizing patterns; a parallel-dimension of strange colours and stunning patterns through which plants communicate with them. With the aid of visual effects, David steps among the swirling vortices of plant scent; communication signals with which plants are inextricably plugged in to the natural world. And using a tuning fork, he demonstrates how plants and insects can even communicate with music. As autumn envelopes the Gardens, fungi reveal themselves not as the enemies of plants but their vital allies. In Kew’s atmospheric Fungarium, David discovers a specimen that has the power of mind control and another that lives underground where it has grown to be so big it can be counted as the largest single organism on the planet. It is 6 times bigger than Kew Gardens itself.

Horizon discovers what your cat really gets up to when it leaves the cat flap. In a groundbreaking experiment, 50 cats from a village in Surrey are tagged with GPS collars and their every movement is recorded, day and night, as they hunt in our backyards and patrol the garden fences and hedgerows. Cats are fitted with specially developed cat-cams which reveal their unique view of our world. You may think you understand your pet, but their secret life is more surprising than we thought.

As the early June sun begins to set over a calm river in Central Hungary, masses of ghostly shapes emerge from their larval cases to take to the air for the first time. They are mayflies and in a spectacular display, thousands of them demonstrate how the very first wings were used. From the stunning aerobatics of hoverflies in an English garden to the mass migration of purple crow butterflies in the valleys of Taiwan, this episode tells the tale of the first animals ever to take to the air. Unique footage reveals the lightning fast reactions of bluebottles and hoverflies, filmed with one of the world's fastest cameras, and Sir David Attenborough handles the world's largest (and perhaps most ferocious) insect - the Titan beetle.

Open your eyes to the bizarre, ferocious and surprisingly beautiful world of the invertebrates, a ground-breaking exploration into a spectacular miniature universe never normally seen but teeming all around us. In the first episode, the story of the land-living invertebrates. Discover the private life of Europe's dramatic leopard slug, a common garden resident with a truly bizarre end to its marathon mating ritual; watches the courtship ballet of tiny springtails on the underside of a leaf; sees swarms of bright red South African millipedes find partners, and in the caves of Venezuela meets the giant bat-eating centipede.