Daichi Shou is a delivery driver working mountain routes near Himeda ridge — ordinary by every measure. That changes when an accident on his delivery run leaves him waking up in a taxi, passenger-seat, next to a woman named Michi who claims he is a genius racing navigator. He is not, but goes along with it. Under his guidance, she gets better, and other skilled women drivers start taking notice. The question becomes which one he will commit to steering toward a championship.