Nick and Nora Charles the bantering, romantically involved detective duo has become a well-used trope in literature, stage, screen, and television ever since. The characters first appear in Dashiell Hammett's best-selling last novel "The Thin Man" (1934). Nick is an alcoholic former private detective who retired when he married Nora, a wealthy Nob Hill heiress. Hammett reportedly modeled Nora on his longtime partner Lillian Hellman, and the characters' boozy, flippant dialogue on their relationship. (The novel also mentions that Nick was once a Pinkerton detective, as was Hammett.) The novel is considered one of the seminal texts of the hard-boiled subgenre of mystery novels,
Allan Pinkerton agency's later reputation for anti-labor activities, Pinkerton himself was heavily involved in pro-labor politics as a young man. Though Pinkerton considered himself pro-labor, he opposed strikes and distrusted labor unions. Allan Pinkerton was so famous that for decades after his death, his surname was a slang term for a private eye. The "Mr. Pinkerton" novels, by American mystery writer Zenith Jones Brown (under the pseudonym David Frome), were about Welsh-born amateur detective Evan Pinkerton and may have been inspired by the slang term. Pinkerton produced numerous popular detective books, ostensibly based on his own exploits and those of his agents.