Keum Sae-rok

Soo-hyun, who has recently moved into a new house, buys a used washing machine through a second-hand app but finds out it doesn't work. Annoyed by the seller's irresponsibility, she leaves a comment calling the seller a con man, and reports it to the police. Little does she know that the seller is a psychopathic serial killer who uses an online second-hand market to lure his victims. Her comment renders his hunt for a new victim all but impossible so she becomes his next target. She starts receiving obscene phone calls, countless unwanted food deliveries, and strange men knocking on her door looking for a good time. A trip to the sender's address proves deadly serious when the police and Soo-hyun find a man’s dead body.

Two best friends, So-yool and Yeon-hee, dream of becoming the top artists in Seoul together. But their friendship doesn't last long as Yoon-woo, So-yool's first love and songwriter, falls in love with Yeon-hee and her voice. So-yool's feeling of jealousy and inferiority towards Yeon-hee grows by the day, and she eventually makes a drastic decision to bring the two lovers down.