Geographer Nicholas Crane presents a 13-part journey around the coast of the United Kingdom, uncovering stories that have made us the island nation we are today. He is joined by historian Neil Oliver, anthropologist Alice Roberts, zoologist Miranda Krestovnikoff and archaeologist Mark Horton. This first leg of the journey takes us 330 miles from Dover to Exmouth: Britain's front line. Nicholas Crane and a group of scientists investigate the once top secret constructions at the front line of Britain's air defences. Neil Oliver travels to Alderney in the Channel Islands to uncover the horrific history of Nazi atrocities there. Miranda Krestovnikoff goes diving in search of cuttlefish just 100m off the shore. Anthropologist Alice Roberts is prospecting for oil on the Jurassic Coast, and archaeologist Mark Horton explores the astonishing growth of Portsmouth as it became the home of the Royal Navy.