Maritime archaeologist Matt Carter explores the West Coast's treacherous sea-faring history. Meanwhile, Oliver discovers a secret beach and goes out on a limb on coastal cliffs. Geologist Hamish Campbell encounters a school hanging on for dear life on the edge of the Tasman Sea in the tiny town of Granity, near Westport.

Oliver has his world turned upside down in Pauanui and marine biologist Jacky Geurts delves into Whangamata's mangrove wars and gets to grips with the treacherous surf rip at Hotwater Beach. Campbell also digs for this country's earliest human history on Great Mercury Island.

Oliver goes on a wild goose chase and uncovers the hidden history of a remarkable singing star and historian Riria Hotere reveals the plan to breed super kakapo on the remote island of Whenua Hou, off Stewart Island's northwest corner.

Oliver tackles a coastal sport like no other and encounters one of the world's great survivors at an exclusive haven for vulnerable species. Hotere tracks down a former skating star on Napier's Marine Parade and goes to sea to see an innovative fishing method.

In the South Island's biggest city, Oliver flies a kite, investigates the origins of the New Zealand accent and goes in search of a toxic arachnid with a tortured love life. Campbell uncovers groundbreaking research on Christchurch's watery past, which could have major repercussions for the future.

Hotere finds out how a city embraced its coast through art, and drops in on a unique surfing contest in Waitara. Marine biologist Jacky Geurts uncovers an underwater creature that has amazing healing properties and Carter uncovers a rare shipwreck with important historical links. Meanwhile, geologist Campbell investigates the energy-rich region's oil industry and Oliver encounters mysterious objects on the Taranaki coastline.