Deadwood City's two most famous peace officers, Calamity Jane and Wild Bill Hickock, get involved in saving the neck of Henry Miller, the local saloon operator. It seems that "Millie" has been promoting a beautiful actress named Frances Fryer, but Frances turns out to be a boy, Francis.
Millie's attempt to cover up is soon unmasked by the angry miners, and only Calamity can cool the crowd with her trusty pistols. To keep the peace, Calamity sets out for Chicago to bring back the miner's real heart-throb, Adelaide Adams. In Chicago Calamity mistakes Adelaide's maid, Katie Brown, for the actress and hauls her back to Deadwood.
Onstage Katie is greeted warmly, but breaks down and confesses that she is not the famous star. Calamity once more has to restore order and persuades the audience to give Katie a chance. They do, and she wins the heart of every male in town including Calamity's dashing love hope, Lt. Danny Gilmartin. Calamity reluctantly overcomes her jealousy over losing Danny and discovers her true love for Wild Bill.