Overview: The Honjo Masamune is perhaps Japan's most legendary sword, but no one knows where it is. Forged in the 13th century, it became the ceremonial sword of the Tokugawa samurai dynasty for 250 years. Since 1868 it was passed on from one generation to the next, but after the Second World War it disappeared. It may have been melted down undetected in occupied Japan, but experts believe it may have made its way to the United States as a souvenir. Today it would be worth millions and collectors hope that the lost sword of the samurai will one day be found.