Mo Fei, a seemingly regular high school girl, possesses a special ability to see a 61-minute countdown to a person's death! To her surprise, this ominous countdown appears on her best friend, Ran Guo'er.

While investigating her best friend's supposed "suicide”, she crosses paths with Jiang Yu, a person dedicated to justice, multiple times. The two help each other, and follow the “suicide” case, unaware of the many cases to come…