James Cook journeys from life as a barefoot farm boy to commanding his own ship on one of the British Empire's first great scientific expeditions. Influential patrons help the bright boy to an apprenticeship in the merchant navy that would make him a ships' master. But with an eye for the main chance Cook switches to the Royal Navy. War with France propels him to Canada, where he discovers his life's work. He revolutionises the accuracy of naval mapping and the way the world is recorded. In further adventures, his genius for precision navigation helps Britain win the war and control of North America. Cook's reward is command of the great scientific expedition to the Pacific Ocean and the newly discovered exotic and sexually liberated Tahiti to record the 1769 Transit of Venus. When the observation is complete, Cook opens secret orders and learns he is to solve one of the world's great mysteries. He must find the Great Southern Continent. The real challenge has just begun.

Captain James Cook sets sail on the history-making adventure in search of one of the great prizes of 18th century exploration, the fabled Great Southern Continent. If Britain can find and map it, they can claim it for the Empire. Cook takes on board an additional passenger, Polynesian priest and fellow navigator, Tupaia. Cook's first encounter with New Zealand's Maori people is a disaster, so he turns to Tupaia who acts as go-between for later landings. Over six months, Cook circumnavigates both North and South islands, proving to Banks and the gentlemen aboard that New Zealand is not the Great Southern Continent. Continuing east into the unknown and landing in Botany Bay, Cook is challenged by what he encounters - Australia's flora, fauna and Indigenous people. Unlike his experience of the Pacific islanders, the Aborigines want nothing to do with the visitors. Cook's landing at Botany Bay will make him an iconic figure in modern history, but not unless he can navigate his way out of the maze of the Great Barrier Reef - a potential disaster that could kill them all.

Cook continues his relentless pursuit of a Great Southern Continent, putting fable and mystery to rest. Despite his great skills sailing and navigating across the world, Endeavour runs aground and is nearly lost. As a patched up Endeavour crawls its way north again, Cook commits the most controversial act of the voyage: he claims the entire east coast of New Holland for Britain, without permission from local inhabitants. To this day, Cook's claim is still not accepted by Aboriginal people. Stopping for emergency repairs in Batavia, infected water turns Endeavour into a death ship. Until now Cook has not lost a man, but by the Cape of Good Hope, Cook has lost over a third of his crew. Back in London, enduring trials of life are also taking their toll on the Cook family. In his absence, Cook's wife Elizabeth must bury a second child. Cook's maps confirm his brilliance. He is promoted to Commander to lead a new voyage that will add an incredible third of the world to the map. It makes him a great British hero but the massive responsibility is taking its toll. He is losing control; only his obsession with discovery drives him on.

Cook's passion for exploration continues as he searches for the mythic North West Passage, but is it a journey too far?