Detective fiction Dupin is a fictional character created by Edgar Allan Poe. Dupin made his first appearance in Poe's "The Murders in the Rue Morgue" (1841), widely considered the first detective fiction story. He reappears in "The Mystery of Marie Rogêt" (1842) and "The Purloined Letter" (1844). C. Auguste Dupin is generally acknowledged as the first detective in fiction. The character served as the prototype for many that were created later, including Sherlock Holmes by Arthur Conan Doyle and Hercule Poirot by Agatha Christie. Conan Doyle once wrote, "Each [of Poe's detective stories] is a root from which a whole literature has
Special Detective Unit Special Detective Unit The Special Detective Unit (SDU) () is the main domestic security agency of the "Garda Síochána", the national police force of the Republic of Ireland, under the aegis of the Crime & Security Branch (CSB). It is the primary counter-terrorism and counter-espionage investigative unit within the state. The Special Detective Unit superseded the Special Branch (which they are still commonly referred to as), which itself replaced the older Criminal Investigation Department (CID), which was founded in 1921. They work in conjunction with the Defence Forces Directorate of Military Intelligence (G2) – the Republic of Ireland's national intelligence