A college student (Elisabeth Harnois) in search of her missing brother follows a trail of clues to the mysterious small town of Riddle, Pennsylvania, where the local sheriff (Val Kilmer) and the town elder (William Sadler) seem determined to impede her investigation. Meanwhile, the more she learns about the abandoned mental hospital on the outskirts of town, the clearer it becomes that the secretive citizens of Riddle have something to hide.