Every year, around 90,000 people are reported missing in Japan. Most of them are found or return home, but thousands of others simply vanish. It seems they don't want to be found. There is even a Japanese word for the phenomenon: "johatsu", or evaporation. Many make meticulous plans for their disappearance and cut all ties with their families to build new lives elsewhere. But why do they do it? And where do they end up? Our reporters spoke to investigators, experts and left-behind families to try to shed light on Japan's "evaporated" people.