The story of Bonnie Parker and Clyde Barrow, the love-struck bandits who rose to fame during America's public enemy era before suffering a violent death at the hands of police, has resonated across generations, spawning films, music, even an annual festival. Starting Sept. 30, some of the most crucial pieces of that iconic American story will be for sale to the public.

The center piece of the auction, which is being held at RR Auction at the Crowne Plaza Nashua, in New Hampshire, is a Colt .38 detective special revolver. The revolver, nicknamed "the squat gun" because Bonnie was squatting on it at the time of her death, was found taped to Bonnie's thigh after she was shot and killed by Texas Ranger Captain Frank Hamer and his posse. Hamer later speculated that it was hidden there because it is one of the few locations "no gentleman officer would search."...