An amateur sleuth mystery features a crime-solving detective who isn’t paid and who has no police or related credentials. The sleuth often stumbles upon the crime or is otherwise drawn in. Amateur sluth mysteries are a staple of the cozy subgenre.
Also known as a heist mystery, the caper mystery is part of the crime genre. Here, the main characters are the perpetrators of the crime (often swindling in the form of theft or burglary), which is usually laudable in terms of audacity or ingenuity.
A gentle, intelligent, and character-driven mystery, cozies may allude to sex or violence, but that action happens elsewhere. In this subgenre, the (often) female (nearly always) amateur sleuth uses her wits to solve a crime that has usually occurred in a small town.
In this subgenre, a private investigator, detective, or inspector (active or retired) uses his/her powers of observation and superior mind to solve what, at the outset, seems like the perfect crime (usually a murder).
The hard-boiled mystery is the polar opposite of the “soft-boiled” cozy mystery. Here, graphic sex and violence are often on the page. The setting is usually urban, the dialogue full of slang and jargon. And the protagonist often a cynical professional.
A crossover of the historical and mystery genres, here the primary events of the story (more than just a flashback) take place in the past. However, mysteries that take place in the future are defacto sci-fi mysteries.
A lawyer is the main sleuth in a legal mystery, which is a close cousin to the legal thriller genre. Often, it’s a defense lawyer, looking to find a way to exhonerate a client, though sometimes it’s a prosecutor who finds himself following an unexpected trail.
Doctors, nurses, medical students, and other health professions set themselves to solving mysteries in this genre, which is often sprinkled with a heavy dose of medical information. Healthcare is usually at the center of the story, usually with some kind of tampering.
Noir is a mood. It’s a sense of place, of people, of things. Gritty. Dark. Cynicism and existentialism. Crime, corruption, and tragically flawed (even anti-hero) protagonists. Not to be confused with the hard-boiled detective genre, though the two share commonalities.
A police procedural is a drama centered around police investigative procedure in solving a crime. Rather than a protagonist who is a lone wolf, an amateur, or a private investigator, here the entire squad is usually involved in the action and drama.
Sometimes the protagonist is an amateur, sometimes a professional, but either way he or she has a gift—one that helps solve mysteries. Also, while the psychic mystery has some overlap with a supernatural mystery, the medium is often the only supernatural element.
A relatively new subgenre, the romantic mystery is a crossover between two hugely populare genres. Often, it’s principally a genre romance that prominently features a crime and mystery.
A sci-fi mystery takes place in a science fiction setting, whether future, near future (speculative), space (a space-opera mystery), or similar. It also would usually crossover with another mystery subgenre (such as detective, noir, or amateur sleuth).
Sometimes with elements of horror or fantasy, a supernatural mystery is centered on the occult or other elements that defy a scientific or natural view of the world. Mystery is at the core of the story, but it’s often obscured by the other fictional elements.
The fictionalized stories of real life criminals and the (usually) sensational crimes they committed. Topics of special intereist include, serial killers, celebrity murders, and extraordinary crimes of various degrees.
Young Adult Mystery
A young adult mystery is not just one of the above subgenres with unsuitable elements for younger readers removed. The scope, language, characters, plot, and motivation will often be uniquely written with the reader in mind.