Jimmy Kudo, the son of a world-renowned mystery writer, is a high school detective who has cracked the most baffling of cases. One day while on a date with his childhood friend Rachel Moore, Jimmy observes a pair of men in black involved in some shady business. The men capture Jimmy and give him a poisonous substance to rub out their witness. But instead of killing him, it turns him into a little kid! Jimmy takes on the pseudonym Conan Edogawa and continues to solve all the difficult cases that come his way. All the while, he s looking for the men in black and the mysterious organization they re with in order to find a cure for his miniature malady.

Doc Agasa takes Conan and his young Junior Detective League pals to an old, abandoned mansion for a treasure hunt. When the pint-size investigators find a mysterious box, they open it and discover it is full of smashed toys and a violently stabbed teddy bear! Conan follows the trail of clues and runs smack-dab into a dead old man in an attic! Who killed the old man, and more importantly, who killed teddy?