Takumi Fujiwara is a skilled street racer, but he suffers a crushing loss against the team Emperor's leader Kyoichi Sudou due to his AE86 experiencing an engine failure. Doubting his abilities, the recent high school graduate is then approached by the Akagi RedSuns' team leader Ryousuke Takahashi, who proposes the formation of a professional street racing team. Although it would be the ideal way to improve as a street racer, Takumi remains undecided. Does the young street racer have what it takes to become a professional? Perhaps Ryousuke and the RedSuns can help him reevaluate his own doubts and misconceptions concerning street racing. However, first and foremost, Takumi decides to settle the score with Kyoichi Sudou... [Written by MAL Rewrite]

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. [Written by MAL Rewrite]

Taking place in the sacred land of street running Kanagawa, once more Takumi Fujiwara will show his driving skills in his now legendary Hachi-roku.

Ichirou Inuyashiki is a 58-year-old family man who is going through a difficult time in his life. Though his frequent back problems are painful, nothing hurts quite as much as the indifference and distaste that his wife and children have for him. Despite this, Ichirou still manages to find solace in Hanako, an abandoned Shiba Inu that he adopts into his home. However, his life takes a turn for the worse when a follow-up physical examination reveals that Ichirou has stomach cancer and only three months to live; though he tries to be strong, his family's disinterest causes an emotional breakdown. Running off into a nearby field, Ichirou embraces his dog and weeps—until he notices a strange figure standing before him. Suddenly, a bright light appears and Ichirou is enveloped by smoke and dust. When he comes to, he discovers something is amiss—he has been reborn as a mechanized weapon wearing the skin of his former self. Though initially shocked, the compassionate Ichirou immediately uses his newfound powers to save a life, an act of kindness that fills him with happiness and newfound hope. However, the origins of these strange powers remain unclear. Who was the mysterious figure at the site of the explosion, and are they as kind as Ichirou when it comes to using this dangerous gift? [Written by MAL Rewrite]