Earth. Year 2050s. After a nuclear war, mankind was reduced to only 3 billions, and is forced to live in areas away from radiation. Bella, a normal 15-year-old student, sees her life taking a 180° turn during a school trip. She discovers a harsh truth about her identity, which will link her to a fishy gang. To unravel secrets about her past, Bella willingly joins them for her own benefits.