Soon after getting a new phone, a woman notices strange things starting to happen. When she investigates, she discovers that everyone who has had her phone number before her has died suddenly and mysteriously.

Some time after completing his mandatory military service, a man receives a distressed call from one of his subordinates, who's also an old classmate.

A prosecutor is falsely accused of sexual assault in a suicide note from a woman that he is convinced was actually murdered. As he investigates her death to clear his name, he realizes that the truth lies in a huge financial scandal.

After losing her laundry store to a fire incident, a single mom Duk-hee receives a call from a bank offering a generous upfront loan so she takes it right away. But soon after, she finds out that she has become a victim of a voice phishing scheme. Devastated, Duk-hee turns to the police for help, only to be more disappointed that there is no hope of retrieving her money. At the moment of despair, Jae-min, the phisher who tricked her, rings her phone once again to tip Duk-hee off about the criminal organization that locked him up and coerced him to make voice phishing calls from China. With that call, Duk-hee makes up her mind to investigate this case for herself and take a plane to China with her friends.

Dae-guk, a nosy man from Apgujeong, and Ji-woo, a cold but skillful plastic surgeon, open a plastic surgery business in Gangnam. Dae-guk is an unemployed man who likes to pry into other people’s businesses.