Daisuke Kanbe, a man of extraordinary wealth, is assigned to the Modern Crime Prevention Headquarters as a detective. It is there that he gets partnered with Haru Katou, a humane detective who values justice above all. The two are polar opposites, and their morals clash time and time again. Haru despises Daisuke for using monetary wealth to solve cases, as he believes that money isn't everything. The two will have to combine their efforts, however, to solve the mysteries that are coming their way.

Since childhood, Haruka Kotoura's classmates have seen her as a creepy and monstrous person. This is due to her ability to read other people's minds—the same ability that drove her parents away, leaving her alone with her grandfather. As a result, she has grown accustomed to the bitter treatment by the people around her, becoming completely cold and unsociable to others. However, everything starts to change when Haruka transfers to a new school. While most are off put by her as usual, she meets Yoshihisa Manabe, who finds her power astonishing. Yoshihisa then proceeds to befriend Haruka, promising to never leave her no matter what happens. Haruka's new experiences of social belonging thus begin, meeting new friends and learning to open herself along the way.

On the islands of Cremona, a vigilante runs amok. Celebrated by some and hunted by others, the notorious Killer B takes justice into his own hands, armed with a sharp blade and superhuman abilities. Unable to apprehend this renegade, the Royal Investigation Service (RIS) calls upon the expertise of Keith Flick, a seasoned, yet eccentric detective who was relegated to the Archives Department following a personal loss. As crimes in Cremona begin to escalate, from stealthy executions of wrongdoers to sophisticated strikes on public figures, it soon becomes clear that there is more than one person responsible. With the help of his impulsive sidekick Lily Hoshina, and unexpected aid from the elusive Killer B himself, Keith begins to unravel plots involving secret organizations, domestic terrorism, and human experiments. When the involvement of the RIS extends beyond the scope of justice, the extent of the government's corruption—as well as the trustworthiness of close allies—are thrown into question.

After escaping certain death, Kei Nagai and his new companion Kou Nakano plot revenge on Satou, their fellow Ajin who is hellbent on world domination. As Satou embarks on a string of public executions, the human race rushes to come up with a solution to stop the immortal villain. Kei discovers unlikely allies in the form of two former adversaries: high-ranking government official Yuu Tosaki, whose extensive research on Ajin gives him a tactical advantage in the fight against Satou, and Tosaki's Ajin assistant Izumi Shimomura. As his faction continues to gather allies, Kei races against time to put a stop to Satou's crusade before it brings about an end to civilization as he knows it.