Shirai Torajiro (Nishino Akihiro), nicknamed Byakko ('White Tiger'), is a former diplomat whose hair turned white overnight after he was subjected to tremendous physical abuse. He dislikes people and is a loner, but during his time as a diplomat, he was trained in areas such as negotiation techniques and behavioural psychology, and conditioned to be the trump card in political diplomacy. Assisted by Sakura Ayano (Kutsuna Shiori), a freeter, Shirai applies his negotiation skills to penetrate the lies of those who have maliciously created trouble, and free people from the depths of despair.