Ichigo Kurosaki is an ordinary high schooler—until his family is attacked by a Hollow, a corrupt spirit that seeks to devour human souls. It is then that he meets a Soul Reaper named Rukia Kuchiki, who gets injured while protecting Ichigo's family from the assailant. To save his family, Ichigo accepts Rukia's offer of taking her powers and becomes a Soul Reaper as a result. However, as Rukia is unable to regain her powers, Ichigo is given the daunting task of hunting down the Hollows that plague their town. However, he is not alone in his fight, as he is later joined by his friends—classmates Orihime Inoue, Yasutora Sado, and Uryuu Ishida—who each have their own unique abilities. As Ichigo and his comrades get used to their new duties and support each other on and off the battlefield, the young Soul Reaper soon learns that the Hollows are not the only real threat to the human world.

Ichigo Kurosaki is an ordinary high schooler—until his family is attacked by a Hollow, a corrupt spirit that seeks to devour human souls. It is then that he meets a Soul Reaper named Rukia Kuchiki, who gets injured while protecting Ichigo's family from the assailant. To save his family, Ichigo accepts Rukia's offer of taking her powers and becomes a Soul Reaper as a result. However, as Rukia is unable to regain her powers, Ichigo is given the daunting task of hunting down the Hollows that plague their town. However, he is not alone in his fight, as he is later joined by his friends—classmates Orihime Inoue, Yasutora Sado, and Uryuu Ishida—who each have their own unique abilities. As Ichigo and his comrades get used to their new duties and support each other on and off the battlefield, the young Soul Reaper soon learns that the Hollows are not the only real threat to the human world.

Dr. Kenzou Tenma, an elite neurosurgeon recently engaged to his hospital director's daughter, is well on his way to ascending the hospital hierarchy. That is until one night, a seemingly small event changes Dr. Tenma's life forever. While preparing to perform surgery on someone, he gets a call from the hospital director telling him to switch patients and instead perform life-saving brain surgery on a famous performer. His fellow doctors, fiancée, and the hospital director applaud his accomplishment; but because of the switch, a poor immigrant worker is dead, causing Dr. Tenma to have a crisis of conscience. So when a similar situation arises, Dr. Tenma stands his ground and chooses to perform surgery on the young boy Johan Liebert instead of the town's mayor. Unfortunately, this choice leads to serious ramifications for Dr. Tenma—losing his social standing being one of them. However, with the mysterious death of the director and two other doctors, Dr. Tenma's position is restored. With no evidence to convict him, he is released and goes on to attain the position of hospital director. Nine years later when Dr. Tenma saves the life of a criminal, his past comes back to haunt him—once again, he comes face to face with the monster he operated on. He must now embark on a quest of pursuit to make amends for the havoc spread by the one he saved.

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.