Conan and his friends notice a young boy looking at an apartment from an alleyway and call out to him. The woman who lives in the apartment asked the boy to call the police if she didn`t exit her room after three men came and left her apartment, as it would mean she was likely dead. Conan and his friends discover scriptwriter Yasue dead from hanging in the room. Based on the situation, Megure determines it was a murder. However, the men Shibakaru, Sakaba, and Habanaka who visited the room all claim she was already dead when they came to the room. The case has three first discoverers...