After her father's death, Ha So Min receives a call in her mother Kim Mi Yang's voice. However, So Min soon realizes that the one behind the phone is Ma Seok Gu using voice technology. Searching for clues, she finds an SOS from Mi Yang and chases a mysterious woman. As secrets unravel, So Min learns that Mi Yang's voice is being exploited by a phishing ring. Consumed by grief and rage, she vows revenge, joining forces with Detective Park Jeong Hun and turning to deepfake herself for a strike.