Private detective Junpei Touma is enjoying a night out at a club when a man stumbles in and collapses on the dance floor. Shocked, Junpei attempts to help him, but the man can only pass him a floppy disk and tell him to give it to someone named Takashiro before dying. Intrigued by the mystery, Junpei starts to investigate along with his coworker, Akira Nagareyama. However, the duo soon discovers that the information on the disk is highly sought after by dangerous individuals willing to use violent tactics to obtain it.