Series in which amateur naturalists explain their passions. Fans of reptiles and amphibians take centre stage, including an enthusiast who has turned his garden into a lizard empire with the aim of helping sand lizards back from the brink. There is also the woman who keeps an eye over her local woodland for Britain's most feared wild animal, the adder; the couple who have created a home fit for the king of newts; and the man who stalks the marshes at night to hear the melodic chorus of toads.