十七世纪初，著名的关原之战爆发。渴望出人头地的作州人新免武藏（木村拓哉 饰）所在军队惨败，为了将好友本位田又八的消息带回家乡，他冒着被当作残党的危险返回，结果被武功高强的僧人泽庵（香川照之 饰）擒住。垂死之际，他得到又八的未婚妻阿通（真木阳子 饰）的救助，并带着这名可怜女子逃跑。途中武藏再度被擒，却于牢狱中自发展开了作为一名武者的修炼。四年后，姫路城主池田（笹野高史 饰）为其赐名宫本武藏，允许他云游四方，磨炼武功。在之后的岁月里，武藏拜访了吉冈清十郎（松田翔太 饰）、柳生石舟斋宗岩（武田铁矢 饰）、日观住持（西田敏行 饰）等名家，更注定重逢宿命的对手佐佐木小次郎（泽村一树 饰）。 一代武术名家的传奇，全新上演……

Ordinary salaryman Hamasaki Mitsuo works for a company which installs vending machines. He complains about his marriage life while at the dentist office. Mitsuo isn't happy at all with his marriage with his wife, Hoshino Yuka, who has the complete opposite personality from him. He doesn't know if he loves Yuka or not. At this time, Mitsuo meets Kono Akari, his ex-girlfriend from his university days, who is now married to Uehara Ryo.