Shayne debuted in the novel Dividend on Death first published in 1939, written by Dresser as Halliday. Fifty Shayne novels were published in hardcover written by Dresser (until 1958) and a variety of ghost-writers. Twenty-seven more were published as paperback originals for a total of seventy-seven. There are also 300 short stories (although many of these are condensed from, or were expanded into, published novels), a dozen films, radio programs and television shows, and a few comic book appearances that included the character.
    -WIKIPEDIA: Michael Shayne

Other recurring characters in the stories are reporter Tim Rourke, Miami Police Chief Will Gentry ( a close friend of Shayne's), Miami Beach Chief of Detectives Peter Painter (a foe of Shayne's), and Shayne's secretary (and occasional romantic interest) Lucy Hamilton.

Michael Shayne stands out from his fictional detective peers primarily due to his professional ineptitude. He is perpetually financially unstable and desperate for any work he can get. A typical story often finds him on the brink of losing his office, or having his furniture repossessed. He is often physically assaulted, and outmaneuvered, which usually results in his embarrassment, especially in the presence of police or other investigators. His frequent misfortunes are largely attributed to his strict ethical code, which prevents him from accepting morally ambiguous cases and the cases he does usually take are desperate clients and wind up being pro bono, leaving him more broke than before. Additionally, his tendency to aid others often leads to regret when those he helps betray him. Despite these setbacks, Shayne manages to maintain a positive reputation based solely on his honesty and integrity. A recurring theme in the narratives surrounding Shayne is his widespread recognition; regardless of his location or the company he keeps, he is invariably known by those around him who are still willing to hire him.
    Michael Shayne Mystery Magazine