Four women in a run-down Korean housing complex have spent years being seen primarily as wives and mothers. When a serial sexual predator begins terrorizing their neighborhood and the police fail to stop him, Miri, Ji-hyeon, Kyeong-ja, and So-hee form an amateur detective team of their own. What begins with tracking a flasher escalates into something far darker when violence intensifies, a severed hand is discovered, and one of the women disappears. Mixing serial-killer suspense with sharp humor, friendship, and social commentary, Salon de Holmes turns overlooked homemakers into formidable investigators determined to expose the monster hiding behind ordinary appearances.