Conan, Ran, and the Detective Boys are taking a vacation on a beach while Kogoro catches fish in a nearby restricted fishing pond. Conan and the others meet up with a woman named Shinobu and her boyfriend. After a few hours the Detective Boys find a note in a bottle saying 'SOS by Shinobu' the Detective Boys find her in a nearby cave but the high tide is coming fast. Can the Detective Boys save Shinobu and themselves before they all drown?
