Mystery/Thriller/True crime are genres in which Langtons International Agency specializes. While these categories are both fiction and non-fiction, they are all focused around crime and mysteries, and are largely suspense driven.
Mysteries can be novels or a collection of short stories. Detective stories and series are the most traditional form of mysteries, which feature a professional cop, private investigator, or detective who solves a crime. These books lend themselves to series, as they have protagonists who can solve a different crime for each book.
Thrillers differ from mysteries in that they do not always have a specific crime or case to solve. Rather, they are suspense stories that are filled with action and cliff hangers. Examples of thrillers include stories of heists, military or terrorist attacks, and criminals on the run.
True crime is a non-fiction category as they are written about real crimes, murders, and other cases. The author will have done extensive research, or will have a personal connection to the case. True crime books will look into the criminal or suspect, and the victim, reveal their backgrounds. It will include facts, but also a narrative arc detailing the crime.
Some examples of mystery/thriller/true crime represented by Langtons International Agency. Art in the Blood a Sherlock Holmes 5 book series by Bonnie MacBird (Harper Collins). The Medina Device by TJ Champitto. Roll the Dice by Wayne Avrashow. A Dark Knight in Aurora by William Reid (Skyhorse). I Would Find a Girl Walking by Kathy Kelly and Diana Montane(Berkeley Publishing). Dancing on Her Grave by Carolina Sarassa and Diana Montane (Berkely Publishing) Movie Showtime.