Eliot Ness is best known for his fight against organized crime in what city?

Eliot Ness (April 19, 1903 – May 16, 1957) was an American Prohibition agent, famous for his efforts to enforce Prohibition in Chicago, Illinois, bringing down Al Capone. His co-authorship of a popular autobiography, "The Untouchables", which was released shortly after his death, launched several television and motion picture portrayals that established Ness's posthumous fame as an incorruptible crime fighter.

With corruption of Chicago's law enforcement agents epidemic, in 1929 Ness went through the records of all Prohibition agents to create a reliable team (initially of 50, later reduced to 15, and finally to just 11 men) called "The Untouchables." Raids against illegal stills and breweries began immediately. The efforts of Ness and his team brought major damage to Al Capone's operations. Ness's efforts eventually led the IRS to prosecute Capone for income tax evasion,

Al Capone promised Ness that two $1,000 notes would be on his desk every Monday morning if he turned a blind eye to Capone's bootlegging activities (roughly $29,000 a week in today's money). Ness refused the bribe and in later years struggled with money; he died almost broke at the age of 54. Ness and his role in bringing down Al Capone had been largely forgotten at the time of his death in 1957, and no Chicago newspaper carried news of Ness's death. His heroic reputation only began with the posthumous publication of the 1957 book he had co-written with Oscar Fraley.