Hundreds of silver fish rain down on a remote community in Australia, whales seem determined to strand themselves, and Alpine ibex scale a dam.
The Amazon is the world’s largest rainforest and one of its most biodiverse environments, home to anacondas, sloths, caimans and dolphins.
With pollution above and habitat degradation below, bird species face an uncertain future. Explore the lives of pelicans, barn owls and vultures.
Autumn on the tundra is mating season for the mighty musk oxen. Elk, capercaillie and deer also battle for opportunities to breed.
Investigate rumours from the old Soviet Union - from mountain wild-men to zombie dogs - and enter a world where nothing is quite as it seems.
Revisit the remarkable Mexican cave decorated with shimmering 11-metre crystals. Could it hold the key to the origins of life on earth?