Plot
Act I
In Indian territory in 1906, cowboy Curly McLain looks forward to the beautiful day ahead as he wanders into farmgirl Laurey Williams's yard ("Oh, What a Beautiful Mornin'"). He and Laurey tease each other, while Laurey's Aunt Eller looks on. There will be a box social dance that night, which includes an auction of lunch baskets prepared by the local girls (to raise funds for a schoolhouse). The man who wins each lunch basket will eat the lunch with the girl who prepared it. Curly asks Laurey to go with him, but she refuses. He attempts to persuade her by telling her that he will take her in the finest carriage money can buy, "The Surrey With The Fringe On Top", but she teases him about it until he says he made it up to get back at her, and Laurey flounces off, not realizing that Curly really does own such a rig.
The sinister and dark-hearted farm hand Jud Fry has set his sights on Laurey and asks her to the dance. She accepts to spite Curly, despite being afraid of Jud. Meanwhile, cowboy Will Parker returns bedazzled and souvenir-laden from a trip to modern "Kansas City". He won $50 at the fair, which, according to his girlfriend Ado Annie's father, is the money he needs to marry Ado Annie. Unfortunately, he spent all the money on gifts for her. Ado Annie confesses to Laurey that while he's been away, she has been spending a lot of time with Ali Hakim, a Persian peddler. Laurey tells her she'll have to choose between them, but Ado Annie insists she loves them both ("I Cain't Say No"). Laurey and her friends prepare for the social, while Gertie flirts with Curly (her obnoxious laugh floating in to taunt Laurey). "Many a New Day" is Laurey's response to her friend's worry that she's overcome by Curly and Gertie's flirtation; her vain attempt to assure them she doesn't really care for him.
Ado Annie's father, Andrew Carnes, discovers her with Ali Hakim. After questioning Ado Annie about her relationship with the peddler, he forces Hakim at gunpoint to agree to marry Ado Annie. Hakim and the other men conclude that "It's a Scandal! It's a Outrage!" Curly discovers that Laurey is going to the box social with Jud and tries to convince her to go with him instead. Afraid to tell Jud she won't go with him, Laurey playfully warns Curly off ("People Will Say We're In Love"). Hurt by her refusal, Curly goes to the smokehouse where Jud lives, and Curly suggests that since Jud does not feel appreciated, he could hang himself and everyone would realize how much they care about him ("Pore Jud is Daid"). Their talk turns into an ominous confrontation, punctuated by alarming but harmless gunplay. Once Curly departs, Jud's resolve to win Laurey becomes even stronger – he is tired of being on his own in his "Lonely Room".
Confused by her feelings for Curly and her fear of Jud, Laurey purchases a potion from Ali Hakim guaranteed to reveal her true love. She muses on leaving her dreams of love behind and joining the man she loves ("Out of My Dreams"), then falls asleep under the influence of the potion ("Dream Ballet"). She first dreams of what marriage to Curly would be like. Her dream takes a nightmarish turn when Jud kills Curly, and she cannot escape him, confused by her desires. The dream makes her realize that Curly is the right man for her, but it is too late to change her mind about going to the dance with Jud; he has come for her, and they leave for the box social.
Act II
At the social, the menfolk join in an upbeat barn dance. A rivalry between the local farmers and cowboys over fences and water rights has led to tension. Both sides state the merits of their way of life, while Aunt Eller tries – and eventually succeeds – in getting them to make peace ("The Farmer and the Cowman"). Laurey is upset when she sees Curly at the dance with Gertie Cummings, a silly girl with an obnoxious laugh. The auction starts out frivolously but becomes much more serious when Laurey's basket comes up for auction. Jud has saved all his money for months so he can win Laurey's basket. Curly is so determined to outbid Jud that he sells his prized possessions: his saddle, his horse, and even his gun; without these, Curly can no longer be a cowboy and will have to become a farmer. Curly outbids Jud and wins the basket. Will bids $50 on Ado Annie's basket in hopes of getting her for a wife, but without the $50, he no would longer have the money her father insisted he needs to "purchase" marriage with Ado Annie. Desperate to be rid of Ado Annie, the peddler bids $51 and gets the basket so that Will can approach Andrew Carnes with his $50 and claim Ado Annie as his bride. Later that night, Will and Annie work out their differences ("All Er Nuthin'").
Jud confronts Laurey about his feelings for her. When she admits that she doesn't return them, he threatens her. She then fires him as her farm hand, screaming at him to get off of her property. Jud furiously threatens Laurey before he departs. Laurey bursts into tears and calls for Curly. She tells him that she has fired Jud and is frightened by what Jud might do now. Curly, seeing that she has turned to him for guidance and safety, reassures her and proposes to her, and she accepts ("People Will Say We're In Love" (Reprise)).
Three weeks later, a drunken Jud reappears the morning after Curly and Laurey's wedding. He attacks Curly with a knife. As Curly dodges a blow, Jud falls on his own knife and dies on the spot. At Aunt Eller's urging, the wedding guests hold a makeshift trial for Curly. The judge, Ado Annie's father, declares the verdict: "not guilty!" and everyone rejoices ("Oklahoma!") in celebration of the territory's impending statehood. After more rejoicing, Curly and Laurey depart on their honeymoon in the surrey with the fringe on top.
