A street urchin attacks and damages luxury cars, and the case is handed to Takasugi in the Juvenile Division. Investigators find a match between the youth's fingerprints and a woman known as the Love Hotel Killer who has been killing her clients. Meanwhile, Jack is called to examine Koichiro Tsuzuki, the young head of the Tsuzuki corporation who has developed a large carbuncle-like tumor on his abdomen which resembles a human face. Some nights he mysteriously disappears for hours. Meanwhile, a beautiful woman calling herself Ryuko, seduces and kills men who cheat on their wives. Later, Jack encounters Mariko, a homeless teenager, who asks him to help her wounded friend Ryuko, whom he discovers has a carbuncle similar to that of Koichiro. When Jack returns to the Tsuzuki residence he finds Ryuko there and the carbuncle then changes her back into Koichiro. Jack determines that Koichiro suffers from a dissociative identity disorder and operates to remove the tumor, but during the operation, the personality of Jun, a street urchin surfaces and he escapes. Suddenly, the police arrive to arrest Koichiro Tsuzuki who has the same fingerprints as the urchin and serial killer on suspicion of the recent murders. Jun attacks the police and is shot, transforming back into Koichiro before dies.
Kuroo Hazama, also known as "Black Jack," is a legend in the medical world. Famous for being one of the best, as well as not having a license, Hazama and his assistant Pinoko save countless lives that other doctors cannot... for a price; an exorbitant price, in fact, which causes many to view the genius as greedy and heartless. Despite these claims, however, none can deny his skill and the lengths that he will go to treat his patients. This dark medical drama tells the story of the ominous and mysterious world of underground medicine as Black Jack risks his life to cure some of the most bizarre diseases imaginable, even if it means breaking every law in the process.
