Sony Pictures has taken the sheet off its ghostly thriller, Silent Hill. A trailer for the movie, scheduled to spook theaters April 21, is now viewable on the movie's official Web site. The film is based on Konami's popular survival horror series, the most recent of which was 2004's Silent Hill 4: The Room. Silent Hill follows the game franchise's haunting formula, namely terrorizing its audience by taking them around haunted locations populated by otherworldly beasts. Not much is given away by the trailer, which shows vignettes of eerie images that retain the game's frighteningly dreary look. The film stars Deborah Kara Unger (The Salton Sea) as a mother searching for her missing daughter in the quaint (and totally evil) town of Silent Hill. The movie also features Sean Bean (The Lord of the Rings), and is being directed by Christopher Gans (Brotherhood of the Wolf).