At the end of the 19th century, the world's largest sapphire, the "Fist of Blue Sapphire," sank into the waters near Singapore along with a pirate ship. When a local tycoon recovered it and displayed its true form on stage, a murder occurred near the Marina Bay Sands hotel. At the scene, a blood-stained notice from the phantom thief Kaitou Kid was left behind. Meanwhile, Ran and Sonoko visited Singapore to watch the karate championship held there. Conan, who was unable to travel abroad due to not having a passport, was supposed to stay home. However, Kid, who intended to use him, forcibly brought him to Singapore through a magical method. With no choice but to comply if he wanted to return to Japan, Conan had his glasses, watch, and clothes taken away and was disguised. When Ran, unaware of his true identity, asked for his name, he hastily gave the alias "Arthur Hirai." Kid obtained information that the sapphire was hidden in the underground vault of a certain mansion. Thinking it would be an easy infiltration, he instead encountered an extremely dangerous trap. Standing in his way was the strongest karate master with an unbeaten record of 400 fights—Kyogoku Makoto. What fate awaits Kid...? After that, as if foreboding something ominous, the water gushing from Singapore's symbol—the Merlion—turned a vivid crimson red!