Workaholic businessman Tsutomu Minagawa is nearing retirement age. One day, while driving his habitual route to the office, he hits a young girl on the spot where the road curves. Although she fortunately escapes with only minor injuries, Minagawa is unable to recover from the shock of his first ever car accident and the harassment of the girl's grandfather. He stops going to work. Instead he goes to the scene of the accident, armed with a stepladder and rags, and begins to clean the traffic mirror. The dirt obscuring it was responsible in part for his collision. As he leans towards the mirror, he notices the words engraved on it: "In memory of Hazuki Kumashiro." Hazuki's parents used their reparation money to put up the mirror, hoping to protect others at the intersection where their daughter was killed. Feeling bad about his previous disregard for traffic mirrors, Minagawa checks out the traffic safety situation all over town. Obsessed with his new mission, he withdraws the family savings and sets out to wipe all the traffic mirrors in Japan...