In an alternate version of 1949 Japan in which World War II never happened, the Japanese capital of Teito is home to both an ultra rich upper class and the dirt poor masses. The city is thrown into a state of panic when a phantom thief called “The Kaijin (Fiend) with 20 Faces” (K-20 for short) begins to use his mysterious abilities to steal from the rich and give to the poor. One day a circus acrobat named Heikichi Endo (Takeshi Kaneshiro) is framed for K-20’s crimes and becomes determined to clear his name. He teams up with K-20’s next target, a wealthy duchess named Yoko Hashiba (Takako Matsu) and her detective fiancé (Toru Nakamura), to take K-20 down once and for all.

一场车祸夺走了岩本聪母亲的生命，岩本聪（本乡奏多 饰）也因此致残，活在自闭的小世界里，连上学都成为了负担。父亲痛爱儿子，研制出机械人H603给他作伴。岩本聪干脆远程遥控这个机械人，让他替代自己上学。
H603来到学校，对周围的事物感到好奇，同学们都叫他“丝柏人”。岩本聪用电脑技术，配合在丝柏人身上应付各种现实生活中的际遇。 丝柏人认识了纯（多部未华子 饰）——一个霸道帅气的女生，岩本聪通过丝柏人同纯开始了默契的交流。
但是，一个可怕的流言摧毁了岩本聪、丝柏人和纯之间的关系。丝柏人能否脱离险境，岩本聪能否获得心灵的救赎，走出心理阴影，事情充满变数……

French silkworm trader Hervé is married to the beautiful Hélène. When an outbreak of disease ravages European silkworms, Hervé must travel to Japan to retrieve healthy eggs. After a long journey, Hervé finally arrives at a village where he can buy them. He becomes infatuated with a young concubine and goes to great lengths to see her again. But, when war breaks out in Japan, the concubine flees, forcing Hervé to return home to his wife.