Jirokichi Suzuki, Sonoko's uncle, invites Conan, Ran, the Junior Detective League, and others to ride Bell Tree, the largest airship in the world, for a six-hour trip to Osaka. However, Kid has his eyes set on the Lady of the Sky, a jewel aboard the vessel. Also, the mysterious terrorist group known as Red Siamese Cat hijacks the ship and accidentally releases a deadly virus which had already spread on Ran, a news reporter, and a flight attendent on the ship. The Red Siamese cats are releasing smoke to make it seem like the ship is filled with the virus. The ship is flying towards Osaka and spectators are evacuating and calling the ship, 'The flying cloud of virus.' Meanwhile, Kid has tricked Ran into thinking that he is Shinichi. Does it mean that he has stolen Ran's heart? With Time Limit of six hours, Conan is bound for the ride of his life!