Kaitou Kid is at it once more, with his sights set on the Crystal Mother - the biggest topaz in Europe - that belongs to Queen Selizabeth of the Principality of Ingram. He plans to carry out the heist while the Queen is traveling by train from Tokyo to Osaka. Complicating matters, the Queen has already hidden the precious gem somewhere on the train, which puts Kid's skills to the test. Meanwhile, among the passengers on the train is Conan Edogawa, who suspects the notorious phantom thief and starts his own investigation. Inspector Ginzou Nakamori is equally primed for a fresh face-off with the crafty thief.