10 years ago, five girls were kidnapped by a Yō Haibara, a suspected serial killer, from their rooms in a mysterious sanatorium on Rougetsu Island, located south of Honshu. They were eventually rescued by Chōshirō Kirishima, a detective pursuing the criminal. Several years after the incident, two of the girls, Marie Shinomiya and Tomoe Nanamura, died mysteriously. The three remaining girls, Ruka Minazuki, Misaki Asō and Madoka Tsukimori, all now 17 years old, return to the island to recover their lost memories and find out more about their kidnapping. Chōshirō also returns to find Ruka in her mother's request.
Following the premise of the previous installments in the franchise, the player is expected to fight off hostile spirits using the signature "weapon" of the series, the "Camera Obscura", along with a new weapon- the Spirit Flashlight, a "torch" with the power to exorcise spirits using moonlight. The player uses the Wii Remote and Nunchuk to aim the camera and flashlight, creating a more realistic and tactile experience. Not all spirits encountered are hostile, and the player will be able to tell the difference depending on the color of the glow of the on-screen Ghost Filament. As with the previous titles in the series some photos of "seals", or "mists" on doors, may offer clues to progressing further in the level.
Source: Wikipedia, "http://en.wikipedia.org/wiki/Zero:_Tsukihami_no_Kamen," available under the CC-BY-SA License.