Mason's first challenge brings him to Phnom Penh, the capital of Cambodia, where he will be getting to grips with a very different kind of cab - the tuk-tuk. Living and working with local driver, 46-year old Polo Doot, Mason takes his life in his hands as he learns to drive what is essentially a converted scooter on the chaotic streets of Phnom Penh. Through the eyes of his host, Mason discovers a country where inequality is surging, as the wealthy elite profit from a property boom, while a third of the population still lives on less than a few dollars a day. Mason faces an emotional and sometimes terrifying journey as he adapts to life in the Cambodian slums, where deep fried tarantula appears on the menu and where traffic mayhem is commonplace. By the end of his stay, the Cockney cabbie has to take paying customers as a fully fledged Cambodian tuk-tuk driver.

Mason gives up his black taxi to work in one of the most remote inhabited cities on earth during the coldest time of the year. In the frontier city of Iqaluit on the edge of the Canadian Arctic, there is no public transport - so the city's small, rugged band of taxi drivers are vital to keeping the population on the move.

An Arctic boom town, Iqaluit attracts many Canadians who are willing to brave the cold, dark and harsh conditions in return for the high wages on offer. It is also a place where the original inhabitants of the Arctic, the Inuit, are still struggling to find their place in the modern world. During his time in Iqaluit, Mason catches a glimpse of the old Inuit world as he joins a hunter out on the sea ice and also spends time in a local soup kitchen, providing an insight into the homelessness, depression and drug abuse that plagues the modern Inuits.

As a full-scale blizzard hits the city, Mason faces driving conditions tougher than anything he has ever experienced. He must battle through temperatues of minus 30 degrees, ferocious winds of 70 miles-per-hour, icy roads and white outs to get the people of Iqaluit safely home.

In this episode, he heads for the palm-fringed islands of Fiji.

As he joins the ranks of the island's capital, Suva and lives with his host Dharmendra Kumar, Mason soon discovers a very different Fiji to the tourist brochures - a country that has struggled with ethnic tensions, political unrest, military coups, a diabetes epidemic and acute poverty. It is all a far cry from the idyllic island life you might expect for a cabbie in paradise.