High-school girl Yuri suddenly finds herself on the rooftop of a high-rise building. She's trapped in a bizarre world surrounded by skyscrapers, where a masked man cracked open a man's head with an axe before her eyes. Finding a way to survive this bizarre world, find her beloved brother, and escape becomes her top priority, but she is beset by danger not just from the mysterious Masks, which possess both inhuman strength and cruelty, but other survivors turned cruel or desparate by the insanity of the high-rise world.
When a popular anchorwoman for a prime time news show becomes the suspect in a murder case, her estranged husband - who has worked as a prosecutor in the past but now works as a public defender - decides to defend his wife.
The Mobile Investigative Unit (known as "MIU") of the Tokyo Metropolitan Police Department attempts to solve cases within 24 hours. Detective Kazumi Shima is selected as a new member of MIU. He is intelligent, with excellent observation and communication skills. Yet, he does not trust other people. He is unable to find a partner in MIU and is ordered to partner with Police Officer Ai Ibuki, who works at a police substation. Ibuki applied for MIU, but he failed. He is in excellent physical condition, but he lacks knowledge and experience as a detective. Shima learns about Ibuki's background and he becomes more nervous. Finally, Shima has his first meeting with Ibuki.
In the small bordertown of Villefranche, lost in the heart of a large forest, crime rate is six times higher than elsewhere in the area. Each new crime Major Laurène Weiss solves with the help of her unusual team makes her sink deeper and deeper into secrets of the area.