When Diana extends an invitation to London to Kogorou and Ran, Conan faces a dilemma as he can't use his usual alias for travel. Ai provides a temporary antidote, allowing him to journey as Kudou Shin'ichi. Accompanied by Professor Agasa, they board a flight to London. Meanwhile, in Japan, Ai resides with Ayumi, unaware of a mysterious man named Kurokawa Youji hot on her trail. As the plot thickens, Mitsuhiko stumbles upon a startling revelation in a magazine featuring a foreign actress resembling Ai, prompting Conan to urgently warn Mitsuhiko to safeguard Ai from approaching Professor Agasa's residence. Determined to protect Ai, Mitsuhiko and Genta spring into action.