日本漫画家千叶彻弥6岁前在中国长大，父亲在印刷厂工作，在日本战败后滞留中国的一年间，全家多亏父亲的一位朋友的舍命照顾。多年后，千叶再次来到中国寻找旧日恩人，寻找时听说因为会日语、在日企工作，恩人受了不少罪。

A mysterious man arrives in a quiet Japanese town. With him, he carries a strange helmet that allows one to re-experience the happiest moment of their life. He goes on to make the village people recall their happy pasts, but his face is lined with worry and a sadness that deepens. What is the secret of this helmet? And what is he trying to do with it?