A nerdy guy who fell in love with the voice of an amusement park worker, goes to the amusement park everyday just to hear that voice. He doesn't know who the owner of the voice is, and has tried to catch the person in action, only to have the amusement park close down. He enlist the help of Muraki and Megumi to locate the owner of the voice by any means. Meanwhile, that amusement park is being investigated for fraud. However, Muraki is currently undertaking research for the director. The whole situation is confusing to Muraki....