Studio Pieona

Kyung-min lives alone in a one-room apartment. One day, she finds traces of a stranger breaking into her room and soon a mysterious murder case begins to unravel.

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 fora good time. A trip to the sender's address proves deadly serious when the police and Soo-hyun find a man's dead body.