Cosy Mystery Korean style.
In a neighborhood mini-market, four women meet for small jobs and good afternoons of chatting. They are respectively 20, 30, 40 and 60 years old. All of them are bored with their husbands who compete with each other in laziness and machismo. So when an exhibitionist is on the loose in the neighborhood, they decide to investigate and have him arrested. And they succeed. A little later, in their apartment building, a serial killer resumes his criminal activities after a few years of pause. His specialty: leaving a smiley face badge near the body of his headless victims.
Together, in order to win the bounty that will pay for the divorce of one of them, braving a thousand dangers, the four Sherlock Holmes of the convenience store will set out to track down the killer.