On 11 March 2011, Japan was rocked by the most violent earthquake in her history and one of the largest ever recorded. The quake itself was just the start of a chain of disastrous events, creating a massive tsunami that slammed the shores of north eastern Japan. Close to 20,000 people were killed or disappeared under waves that reached more than 40 metres high as they smashed their way several kilometres inland. Yet the greatest damage was caused when the tsunami surged over the seawall of Fukushima Dai-Ichi nuclear power station, resulting in a multiple core meltdown that released vast quantities of radioactivity into the atmosphere and ocean. At one stage it even threatened the evacuation and irradiation of Tokyo itself, which would have spelt the end of Japan as we know it. Fukushima is the incredible story behind the twin catastrophes of the tsunami and nuclear meltdown, seen through the eyes of witnesses and victims - from former prime minister Naoto Kan, the plant director and senior engineers of Fukushima Dai-Ichi, the elite firefighters who risked their lives to avert the ultimate nuclear nightmare, to the mother excavating the wreckage as she looked for her daughter's remains.