The Roaring '20s were a time of raucous parties, dangerous bootleggers, gangsters and generally wild behavior. They were also very superstitious times. Many people attended seances, consulted psychics and mediums, and were fascinated with magicians during this period in American history. This era gives a writer the perfect setting for a mystery full of unexpected events and surprises. The story should contain a host of deep characters, for example, a young cabaret singer with an independent streak and a chip on her shoulder, and an "honest" bootlegger who runs alcohol just for the money and keeps out of the gangster scene. They could meet at a seance where everything goes horribly wrong and psychic turns up dead.
Framing the innocent thief can take place in any time period in history, anywhere in the world. The basic plot line involves a jewel (or art or bank) thief breaking into a building for the latest job and finding a very prominent, wealthy or famous person dead on the floor. Just as the thief is about to leave, abandoning the body and whatever he or she came to steal, the police show up and attempt to arrest the thief for murder. The thief narrowly escapes and goes on a mission to discover who really murdered the dead person and why. A writer can easily fill this plot with seedy characters, dank hiding places, despicable people both wealthy and poor, and make least suspect character the murderer, leaving subtle clues throughout the story.
In this plot, the detective is an ordinary person kidnapped by a criminal. The criminal may be guilty or innocent in the end, but the plot centers around the kidnapped character being forced to investigate a crime the kidnapper claims not to have committed. Perhaps the criminal was framed by a gang buddy, a high society maven, or maybe he or she was involved in the crime but did not commit the actual act. This plot works because it can go in many different directions. The author can trot down each path before crossing over to a different one, backtrack and throw the reader plenty of curve balls. Writers can also easily adapt this plot to any time period, place or level of society.