A mystery is primarily concerned with solving a crime or a puzzle. The standard mystery generally revolves around a murder which must then be solved by policemen, private detectives, or amateur sleuths. Typically, the viewer is presented with a series of likely suspects, some of who are "red herrings," -- persons with motive to commit the crime who didn't actually do it -- and attempts to solve the puzzle along with the investigator. Sometimes, the viewer is presented with information not available to the main character, in which case, the film's tone is generally one of suspense, drama, comedy or some element other than traditional mystery. Despite the fact that mysteries depend strongest on surprise, numerous established and repeated character stereotypes and situational cliches fuel them. They include famous, brilliant private eyes (Sherlock Holmes, Charlie Chan, Phillip Marlowe, Hercules Poirot) who never lose a case, femme fatales, murderous hired help (The Butler did it...), and recurring motivations like greed, lust and revenge by the character most unlikely to commit a crime, but who does so nonetheless.