Nick Crane explores the exotic Isles of Scilly - 28 miles beyond Land's End,
these are England's final full stop. On magical isles with a Caribbean feel,
Nick joins the locals to attempt one of the most bizarre walks in Britain, as
they try to wade on foot through the surging seas from island to island. It's a
challenge only possible at exceptionally low-tide, yet still the seawater
threatens to swamp them.

To discover what life is like on this extreme edge, Nick visits the last house
on the very tip of the most westerly inhabited isle. He pushes beyond the edges
of Britain's history too, walking back in time to the bronze age, as the seabed
reveals evidence of an ancient settlement, long submerged beneath the waves. Is
this the site of the legendary 'Lost Kingdom of Lyonesse', said to be the last
resting place of King Arthur?

On precipitous slopes, beyond the edge of Devon, Coast newcomer and social
historian Ruth Goodman follows in the footsteps of the remarkable Branscombe
cliff farmers, who for generations followed a hardy way of life that's now gone
with the sea breeze. Ruth relives a day in the ceaseless toil of the last man
left on these perilous cliffs, the aptly named 'Cliffie' Gosling, who together
with his trusty donkeys made the steep ascent between land and sea daily until the 1960s.

Mark Horton explores the cutting edge of Victorian information technology in a
celebration of one of Britain's most audacious engineering achievements. The
titanic struggle to create the transatlantic telegraph service between Britain
and America would eventually herald the birth of global communications, but how
did Brunel's mighty ship, the Great Eastern, manage to lay a cable 2,000 miles
along the seabed to transmit and receive tiny electric signals between
continents? Mark and the team rebuild the ingenious invention which, in 1865,
finally made the transatlantic cable a glorious reality after ten years of
tragic failure.

And, on the dramatic rocky edge of St David's Head in South Wales, Hermione
Cockburn explores the very limits of life on the planet to reveal the
astonishing fossil of a large sea creature - one which lived 300 million years
before the dinosaurs. This discovery helped establish that Britain and America
were once part of the same super-continent, and that the Earth is old enough for
Darwin's theory of evolution - once held to be on the margins of science - to
become central to our understanding of who we are.