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,
Pinkerton (detective agency) of the late 19th and early 20th centuries, businessmen hired the Pinkerton Agency to infiltrate unions, supply guards, keep strikers and suspected unionists out of factories, and recruit goon squads to intimidate workers. One such confrontation was the Homestead Strike of 1892, in which Pinkerton agents were called in to reinforce the strikebreaking measures of industrialist Henry Clay Frick, acting on behalf of Andrew Carnegie. The ensuing battle between Pinkerton agents and striking workers led to the deaths of seven Pinkerton agents and nine steelworkers. The Pinkertons were also used as guards in coal, iron, and lumber disputes in Illinois,