The events of D2 take place in the near future. You are cast in the role of a young woman named Kei, a police officer who specializes in counter-terrorist activities. One day she and her boyfriend (also a policeman) receive an assignment to investigate a murder that occurred in a hotel. The investigation gradually leads to a confrontation with a mysterious evil man who seems to know a lot about Kei's past, which was concealed from her.
The game is a third-person shooter with strong elements of survival horror. Kei uses guns to dispatch enemies and can side-step and roll to avoid their attacks. Ammunition and health kits are rare, and there is a possibility to steal them from the enemies. Kei can communicate with the police station by using her cat, which is a disguised communication device.
D2 was released for the Sega Dreamcast on December 23, 1999 , and falls under the genres of Action & Adventure. Players will experience intense action and suspense as they guide Kei through the game's storyline.