変装した宿敵である「黒蜥蜴(くろとかげ)」

Against this crisis, the jewel merchant requested the protection of Sanae and the security of the diamond from Kogoro Akechi, the solitary master detective representing Japan. Before Akechi keeping watch over Sanae at the hotel, a wealthy, elegant woman calling herself Madame Midorikawa appeared. Akechi, with sharp observation, saw through that Madame Midorikawa was his nemesis Black Lizard in disguise, but Black Lizard also sensed Akechi's identity, sparking a suffocating psychological battle.