Conan, Kogoro and Ran come across the scene of an accident. A man named Takeshi Yaginuma fell to his death from the staircase of a parking structure. On top of the stairs is Misaki Takizawa, who claims Yaginuma attacked her and accidentally fell. During the investigation, it is discovered Yaginuma is a criminal who broke into Misaki's home and murdered her husband, Akira, and stole 100 million yen worth of precious jewels. Kogoro believes Yaginuma attacked Misaki to silence her, but Conan suspects there's something wrong with Misaki's testimony.