Bloody Chronicles Act 1 — Secret Operation is an add-on for a visual novel adventure with elements of a Japanese-style dating simulator. It adds two new characters to the game (Inaho Asaba and Uzair), as well as a new task, during which the characters will have to catch an escaped criminal. The plot tells the story of a certain Koyama Kazuki. He is a young detective who is tracking down a serial killer known as the Phantom. Beautiful girls will also help him in his business. The character may have a romantic relationship with some of them.