In the not so distant future, mankind has advanced to a state where complete body transplants from flesh to machine is possible. This allows for great increases in both physical and cybernetic prowess and blurring the lines between the two worlds. However, criminals can also make full use of such technology, leading to new and sometimes, very dangerous crimes. In response to such innovative new methods, the Japanese Government has established Section 9, an independently operating police unit which deals with such highly sensitive crimes. Led by Daisuke Aramaki and Motoko Kusanagi, Section 9 deals with such crimes over the entire social spectrum, usually with success. However, when faced with a new A level hacker nicknamed "The Laughing Man," the team is thrown into a dangerous cat and mouse game, following the hacker's trail as it leaves its mark on Japan. [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]

Accumulating an impressive series of victories with his AE86, Takumi Fujiwara has imposed himself as street racing's newest rising star. However, his newly found confidence of winning at his home turf of Mount Akina has been put in jeopardy by a new Emperor team exclusively using a car model favored by most professional racing pilots: the Mitsubishi four-wheel drive Lancer Evolutions—also known as Lan Evos. The Emperor team leader, Kyouichi Sudou, looks down on Takumi and regards him as an inferior pilot for driving an antique car that lacks the makings of a true modern race car. Kyouichi's elitist philosophy is also the reason why his team is only made of Lan Evo drivers. Will Takumi be able to keep his perfect track record intact against the highly skilled and mechanically superior Emperor team, or does his hot streak end here? [Written by MAL Rewrite]

The anime's story is set in 2027, one year after the end of the fourth non-nuclear war. New Port City is still reeling from the war's aftermath when it suffers a bombing caused by a self-propelled mine. Then, a military member implicated in arms-dealing bribes is gunned down. During the investigation, Public Security Section's Daisuke Aramaki encounters Motoko Kusanagi, the cyborg wizard-level hacker assigned to the military's 501st Secret Unit. Batou, a man with the "eye that does not sleep," suspects that Kusanagi is the one behind the bombing. The Niihama Prefectural Police detective Togusa is pursuing his own dual cases of the shooting death and a prostitute's murder. Motoko herself is being watched by the 501st Secret Unit's head Kurutsu and cyborg agents. (Source: ANN)