Samurai William: The Adventurer Who Unlocked Japan.In 1611, Londons merchants received an intriguing letter written by a marooned English mariner named William Adams, who had been living in the unknown land of Japan for more than a decade. Seven adventurers were sent to Japan with orders to find and befriend Adams. It was believed he held the key to exploiting the opulent riches of this forbidden country; but when they arrived they discovered that William Adams had gone native.