Shinnosuke Tomari is a former elite police officer in the Metropolitan Police who, after an event that traumatized one of his colleagues, has been "demoted" into the Special Investigations Division, a group that looks into the stranger happenings in the city, particularly the "Heavy Acceleration" events that leave people unable to move that the public have termed the "Slowdown." When he is chosen by the Drive Driver and Tridoron, Shinnosuke transforms into Kamen Rider Drive and is tasked with battling the Roidmudes who wish to take over the world by eliminating humanity.