In North Yorkshire, Helen descends 4500 feet into the UK's deepest mine. On the Kent coast, JB explores the strange beauty of Dungeness. And Jules visits Devon, setting sail from Salcombe.
The trio take up a variety of activities on land and sea - from photographing elusive marine mammal, the porpoise, to surfing at Tynemouth Long Sands.
In south-west Scotland, Helen Skelton heads off-road into the rolling hills of Bainloch Deer Park, home to over six hundred red, sika and fallow deer. Further north, Jules Hudson explores the dark history of HMP Peterhead - Scotland's own Alcatraz. JB Gill gets hands-on with a reconstruction of the Sutton Hoo ship on the Suffolk coast.
JB Gill heads to the Lincolnshire coast to join the Skegness Pier Angling Club during one of their friendly beach competitions. Under the watchful eye of veteran angler Charlie, JB gets a crash course in coastal fishing. In Cumbria, Helen Skelton meets some unlikely coastal heroes - vultures. And in Fife, Jules Hudson unearths Cold War secrets beneath quiet fields, exploring a declassified communications bunker.
JB Gill explores the Sussex coast in Brighton, home to beach huts, saunas and the i360 - Europe's tallest moving observation tower. In Merseyside, Helen Skelton joins the crew of the RNLI's high-speed Shannon lifeboat. Jules Hudson visits the Portsmouth Historic Dockyard on the Dorset coast, uncovering a personal chapter of naval history and tracing the story of his great-uncle George Norcott.
In Anglesey, Jules Hudson explores the site of a 19th-century shipwreck near Moelfre, where over 400 people perished. Helen Skelton learns about the women who helped win the war - not in factories, but in shipyards - in Sunderland. JB Gill begins his journey at Mersea Island Vineyard, where he's introduced to a surprising local speciality - beer brewed with oysters.
On the Lancashire coast, Helen Skelton heads to Fleetwood's Rossall Coastwatch Tower, where she joins the local National Coastwatch volunteers to learn the skills needed to keep eyes on the water. JB Gill explores the cliffs of Porthcawl, South Wales, where layers of ancient limestone reveal a forgotten prehistoric world. In Dorset, Jules Hudson musters his courage for a paragliding flight above the Jurassic coast.
In southern Cumbria, Helen Skelton takes to the skies in a gyrocopter with veteran pilot Roger to explore a coastline often overshadowed by the Lake District to the north. In Cornwall, Jules Hudson joins marine scientists making waves with a serendipitous discovery - disco scallops. Further up the Bristol Channel, JB Gill faces the Somerset coast at Burnham-on-Sea, where tides race in, and mud flats can trap the unwary.