In Kimberley, Western Australia, Tim Flannery walks in primeval tracks along the Dinosaur Coast. Neil Oliver wrestles the southern hemisphere's biggest tides at the surging Horizontal Falls, and Xanthe Mallett explores a unique maritime war grave. Neil also discovers Broome's dark pearling history and the delicate science of pearl cultivation.

Across the glittering waters of Sydney, Neil Oliver explores the network of fortification to protect ‘Fortress Sydney’, and discovers how close the city came to being taken in WW2. Xanthe Mallett learns how to make lime as the convicts did, in her quest to understand the importance of oysters in building the early colony. Tim Flannery reveals the geological secrets of the city’s vast and sprawling harbour and unlocks the riddle of the rivers that had Captain Philip baffled in 1788. Brendan Moar examines an international icon in engineering and design, and reveals the story of those who made the greatest sacrifice. Emma Johnston hunts for tropical fish in Sydney’s temperate and diverse harbour.

Neil Oliver begins this stunning journey through the world’s largest coral reef in the wake of James Cook, and in the hands of the Australian Navy’s hydrography team. Brendan Moar discovers an Australian community overcoming wretched beginnings by renewing island family ties. Tim Flannery is granted rare access to a scientific research zone to examine coral history. Xanthe Mallett dives a spectacular wreck in search of answers about its calamitous sinking. On an idyllic island, Neil Oliver uncovers a bloody tale of cultural misunderstanding. Finally, at the southern end of the Great Barrier Reef, Emma Johnston heads underwater with Google to take the reef into homes around the world.

In the tranquil south east of Tasmania, Neil Oliver probes Port Arthur's harsh penal history. Brendan Moar examines the dramatic grip of lighthouse life on a remote island. Emma Johnston dives into an underwater battleground to see how science and industry are saving the marine neighbourhood.

On Australia’s shiny holiday coast Miriam Corowa investigates the engineering behind the 1970s Florida-style canal system of the Gold Coast. Neil Oliver heads to Peel Island to see the remains of a bleak chapter in history. Xanthe Mallett scours a WW2 fortification at what could have been Australia’s front line, and discovers what life was like waiting for the war to arrive. Brendan Moar dives headlong into a dangerous current to investigate first hand the science of rips. Emma Johnston joins a scientific hunt for dugongs, in the hope of saving them. Finally, Tim Flannery travels to Fraser Island to investigate what’s at the end of the line for the longest sand drift system in the world. NB: Aboriginal and Torres Strait Islanders viewers are advised that this programme contains images of people that have died.

Along this historic stretch of coast, Neil Oliver explores Cape Otway and the beacon that helped birth a nation. Tim Flannery scours the water for evidence of the marine mega-fauna that roamed ancestral Port Phillip Bay. Brendan Moar uncovers the history of the Great Ocean Road, and, armed with his pick, grasps the challenges of building a now world-famous coastal road in the 1920s. Emma Johnston hunts for the delicate Weedy Seadragon and discovers a tragic tale of one artist much captivated by its vivid beauty. On the historic Loch Ard wreck, Xanthe Mallet dives for clues about how and why disaster struck, with only two lives saved, while Miriam Corowa discovers why the coast at Bells Beach keeps pumping out the perfect waves.