While visiting Hachijo-jima, Conan sneaks aboard a security boat heading to the Pacific Buoy, an off-shore facility constructed near the coasts built to connect surveillance cameras used by police forces around the world. However, an engineer gets abducted! An eerie sound of a propeller hums underwater as a dark figure begins to creep toward Ai Haibara... When the forbidden Black Box is opened, the sealed-away past will surface above the treacherous waves!