Sir David Attenborough explores our grasslands, some of Britain and Ireland’s most beautiful places. From the coastal flower meadows in the Scottish Outer Hebrides to the rich open landscapes in the mountains of south-west Ireland, we enter surprising and dramatic worlds inhabited by creatures great and small.

Whether it’s rough and untamed, flower-rich, or farmed, rooted in chalk or scree, our varied grasslands set the stage for spell-binding spectacles. In Dorset, an enchanting bee rides through a meadow on a tiny broomstick, and on a sheltered slope in Northumbria, adders perform a surprisingly delicate courtship routine, rising up and entwining before using their extraordinary male anatomy to mate. As darkness descends, thermal cameras reveal new footage of rabbits evading the foxes that hunt them at night.

Over in Gloucestershire, we uncover a remarkable conservation success story. Once extinct in our isles, our shores are now believed to be home to one of the largest concentrations of large blue butterflies anywhere in the world. But these winged wonders are the product of an extraordinarily sinister lifecycle; their survival relies on a game of deception with a red ant, which is tricked into adopting the butterfly’s unassuming but predatory caterpillars into its nest. The ants soon pay the price, as the caterpillar begins a six-month gorge on their larvae.

In County Kerry, spectacular battles are captured between red deer stags, the largest wild animals to walk our isles, whilst in Cambridgeshire, we reveal how feisty herds of free-ranging horses are restoring our lost wild grasslands.

As modern agriculture replaces these precious habitats, the grasslands of the British Isles are under threat. This episode shows just how important our different types of grassland are to the species which call these islands home.