Ae Ran, a mother who is proud of her son, hears the shocking news that Do Hoon, her son who left the military, has developed schizophrenia. Afraid of losing her perfect daily life, Ae Ran decides to hide her son's illness. Ae Ran's secret life seems to be smooth but starts to change when Kyeong Hwa, the only person who knows her secret, appears, gradually turning her anxiety into madness.

In a shabby neighbourhood where serial murders are disguised as lonely deaths occur, an elderly priest who hears the confession of a criminal and a middle-aged female detective work together to find and chase down the culprit.

'Notic Wave' is a virtual facility that processes noise. One day, Manager Oh from the facility takes his own life while agreeing to pay compensation with the local residents for the noise pollution. Tae Seung, a snobbish office worker who becomes his successor, is also keen on a compensation agreement, but a factory manager and farmer block his way. The suspicious attitudes of these two characters continue to raise suspicions that it may be related to the death of Manager Oh. Tae Seung continues the on-site investigation of the village in earnest, and as the shocking truth unfolds, the case gradually falls into a labyrinth.