Takumi Fujiwara finally joins Ryousuke and Keisuke Takahashi to create "Project D." Their goal is twofold: Ryousuke wants to develop his "High-Speed Street Racing Theory," while Keisuke and Takumi aim at improving their driving skills by facing powerful opponents on dangerous roads. The idea of Project D is to challenge street racing teams from other prefectures to improve both their uphill and downhill records. In order to attract the attention of the best racing teams, Ryousuke creates a dedicated website to announce the future battles of Project D and post the team's results. The fourth season of Initial D details the hardships and successes of the members of Project D as they try to become the best street racing team outside of Gunma Prefecture. Takumi Fujiwara and brothers Keisuke and Ryousuke Takahashi have formed "Project D", a racing team aimed at bringing their driving skills to their full potential outside their prefecture. Using the internet, Project D issues challenges to other racing teams and posts results of their races. Managed by Ryousuke, the team has Takumi engaging in downhill battles with his AE86, while Keisuke challenges opponents uphill. Among their rivals are the Seven-Star Leaf (SSR) and Todo-juku.Meanwhile, Takumi is caught off-guard on Mount Akina when he encounters his father Bunta and his newly acquired Subaru Impreza WRX Type R Version V.