MEITANTEI CONAN: HAIBARA AI MONOGATARI - KUROGANE NO MYSTERY TRAIN

The movie focuses on Ai Haibara's past and reconstructs the Mystery Train arc from the television anime, which shows Haibara and Conan meeting for the first time. The movie also includes scenes from the Kurogane no Submarine (Black Iron Submarine) film. — Description from AniList community (anilist.co).