Tomboy Calamity Jane is best friends with Wild Bill Hickok but thinks she is in love with Lt. Danny Gilmartin. Calamity boasts and brings an actress from Chicago who is chased by Bill and Danny.
On a stagecoach Calamity Jane (Doris Day) sings “The Deadwood Stage.” Calamity claims that she shot thirty Indians and talks with Will Bill Hickok (Howard Keel) about a cigarette picture of Adelaide Adams. Calamity learns that Lt. Danny Gilmartin (Philip Carey) was shot off his horse and goes after him. She rescues him from Indians.
Saloon owner Henry Miller (Paul Harvey) presents Francis Fryer (Dick Wesson) dressed as a woman, and he sings “Honey Bee.” Men get angry, and Calamity pleads for Henry and says he got Adelaide Adams.
Calamity and Bill sing “I Can Do Without You.” Bill suggests that Calamity buy feminine clothes.
Calamity goes to Chicago. In a show Adelaide Adams (Gale Robbins) sings “Harry.” Adelaide tells her maid Katie Brown (Allyn McLerie) she wants to leave Chicago and that Katie can have her costumes. Katie puts on a costume and sings. Calamity thinks she is Adelaide and hires her.
Calamity brings her to Deadwood and sings “Just Blew in from the Windy City.” Francis knows she is Katie, not Adelaide. Bill keeps his promise to dress as a squaw, and people laugh. Katie sings with a weak voice and admits she is not Adelaide. Calamity persuades the men to give Katie a chance. Katie sings “Keep It Under Your Hat.” Bill lassos Calamity and hoists her.
Calamity invites Katie to stay in her cabin. Bill sings “My Love for You.” Katie offers to fix up Calamity’s cabin and sings “A Woman’s Touch” with Calamity as they clean and paint. Bill and Danny race to go there. Calamity is wearing a dress but is outside. Katie sends Bill out to chop wood. Katie tells Danny that Calamity loves him. Bill comes back in, and they see Calamity in a muddy dress.
On the way to a ball Bill and Calamity sing “The Black Hills of Dakota.” Calamity takes off her coat, and Bill realizes she is beautiful. Danny dances with Katie and kisses her. Jealous Calamity shoots Katie’s cup. At home Calamity takes off her dress, and Bill leaves.
Calamity interrupts Katie’s show and warns her to leave town. Katie shoots Calamity’s glass. Bill leaves with Calamity and says he shot the glass. Bill says that he was in love with Katie. He kisses Calamity, and she likes it.
The next day Calamity sings “Secret Love” and rides to town. Francis tells her that Katie left for Chicago. Danny reads a note from Katie saying that Calamity loves Danny. Calamity rides to catch the stage. She tells Katie that she is going to marry Bill. At the double wedding Calamity, Bill, and Katie sing a medley of songs.
This romantic musical comedy satirizes the rigid male and female roles in the west by showing exceptions. Sex-starved men long for a woman but treat Calamity as a man until she changes her clothes. She comes to realize that one’s best friend usually makes a good partner.