I bought a used item from a killer today Soo-hyun buys a used washing machine online after moving into her new place. When she receives a broken machine, she realizes she’s been scammed and decides to make sure the seller doesn’t get away with it! Eventually, Soo-hyun succeeds in finding the seller’s online account, then leaves warnings that he is a fraudster under all his posts to stop him from selling. From then on, terrifying things start to happen to Soo-hyun. She led an ordinary life with an ordinary job, but everything in her daily life begins to fall apart, and an investigation to find the seller unfolds. Later, Soo-hyun goes to the seller’s pace with Detective Joo, and discovers a dead body… With one used goods deal, her life gets destroyed! Anyone can become a target!