Meitantei Conan: Haibara Ai Monogatari - Kurogane no Mystery Train

Ai Haibara (autonym Shiho Miyano a.k.a. Sherry). A woman with three identities, who boldly faces her destiny. Shiho Miyano (code name: Sherry), a scientist and a member of the Black Organization. The organization was the one that developed a mysterious poison APTX (Apotoxin) 4869, the drug that turned Shinichi Kudo into a little boy! However, when Sherry realizes that the Black Organization has murdered her sister Akemi, she betrays the Black Organization and decides to take APTX4869. The drug turns her into a little girl, and she decides to call herself Ai Haibara in order to hide from the Black Organization. Yet slowly but surely, the Black Organization begins to cast its shadow over her.