The story starts three months before Kudou Shinichi became Edogawa Conan. High school detective Kudo Shinichi and his childhood friend, Mori Ran, hear a male voice shout right after coming out of a nail salon on the first floor of an apartment building. When they rush over to the scene at the entrance of an apartment, cameraman Tsuboichi Yuhei is bleeding from his forehead and his assistant Kishi has collapsed. Shinichi and Ran burst into the apartment to discover that Aida Momoko, the model who lives there, has died. An investigation is conducted. Kishi gives evidence that he had been hit with what seemed like an iron bar by a man who darted out of the room. Tsubouchi says he would like to have the murderer arrested. He is the dead Momoko's brother-in-law. Shinichi feels something is wrong with Tsubouchi and Kishi's statements. If the attacker was the same person, he should have struck Momoko with the bar too, but Momoko was strangled by a pair of hands. This makes Shinichi turn his suspicion toward Tsubouchi. Will he be able to expose the murderer's secret trick and arrive at the truth?