In the last episode of the series, Ellie Harrison visits the Somerset Levels, a newly created wetland in the shadow of Glastonbury Tor, where creatures once on the brink of extinction are now returning thanks to our efforts. She goes on a nocturnal hunt for insects, watches rare egrets and bitterns, and discovers how these former peat diggings have been transformed into a special place for people and wildlife.Ben Fogle goes in search of the slipperiest of all our creatures - the eel; George McGavin tracks down the 'underwater dragon' - the great crested newt; and Ellie joins a team devoted to saving our most endangered mammal, the water vole. She also discovers how our tallest bird, the crane, has been brought back to the West Country after an absence of almost 500 years.