Based on a story by Damon Runyon and the play with songs by Frank Loesser, gamblers try to find a place for a crap game while the Salvation Army tries to reform them.
Men and women dance in New York City, and men use phones to call in bets. A policeman chases pickpockets. Nicely-Nicely Johnson (Stubby Kaye), Rusty Charlie (Danny Dayton), and Benny Southstreet (Johnny Silver) sing “I’ve Got the Horse Right Here” (“Fugue for Tinhorns”). Sergeant Sarah Brown (Jean Simmons) and the Salvation Army sing “Follow the Fold,” and Sarah preaches against drinking and gambling. A salesman offers solid gold watches for one dollar. Sarah gives up, and they march on.
Harry the Horse (Sheldon Leonard) tells Nicely-Nicely and Benny to tell Nathan Detroit that he is loaded and looking for action. Lt. Brannigan (Robert Keith) tells them the heat is on and that he is looking for Nathan’s floating crap game. Nathan Detroit (Frank Sinatra) is told and says he might be able to use the Biltmore garage, but he needs $1,000. Nathan says he could not afford to buy Adelaide a present for the 14th anniversary of their engagement. Nathan, Nicely-Nicely, Benny, and Rusty wonder where they can get the $1,000 and sing “The Oldest Established Permanent Floating Crap Game.” Nathan learns that Sky Masterson is in town and says he makes crazy bets. A waiter brings Nathan cheesecake. He sends Nicely-Nicely and Benny to find out how many pieces of cheesecake and strudel were sold yesterday. Adelaide (Vivian Blaine) sits with Nathan and gives him an anniversary present, a business card. She asks him not to run the crap game. Nathan learns they sold more strudel. He sends Adelaide to rehearsal at the Hotbox with Nicely-Nicely and Benny. Nathan greets Sky Masterson (Marlon Brando), who sits down. They talk, and Sky asks about Adelaide. Nathan asks Sky to bet $1,000 on cheesecake vs. strudel. Sky tells a story how he learned not to take sucker bets. Sky asks him to bet on the color of his tie. Sky says all dolls are the same. Nathan asks Sky why he is not taking a doll to Havana. Nathan bets Sky $1,000 that he can’t take Sarah to Havana. Sky feels suckered.
At the mission Sarah tells Arvide Abernathy (Regis Toomey) that she wants to quit and go home. He says she is up against the best sinners. Sky comes in, and Arvide gives him coffee. Sarah asks his problem, and he says gambling. He says he could be marked as a chump for losing a sucker bet. Arvide says Sarah can solve other people’s problems. She gives Sky some pamphlets to read, and he asks for personal help. She opens the door and says he can come in any time. She says she does not trust him. He says she does not believe that he wants to repent. He says some are all repenters and no sin. He sees a Bible quote and says it is not from Proverbs but Isaiah, and she finds he is right. He says he reads the Gideon Bible in hotel rooms. He says the mission is laying an egg because it has no customers. He offers to provide one dozen sinners for her midnight meeting on Thursday if she will have dinner with him tomorrow night in Havana, Cuba. He says the sinful thoughts are coming from her, and she acknowledges that she is a repressed and neurotic. He asks what the proper man for her will be like. Sarah and Sky sing “I’ll Know.” He says he will know by chemistry. He kisses her, and she stops struggling. As he is going, she walks over and slaps him.
Nathan calls Joey and says he will win the $1,000 bet. At the Hotbox Adelaide and her Alley Kittens dance and sing “Pet Me Poppa.” Nathan asks for Joey’s garage for the game, but he is rejected. Adelaide finds Nathan in her dressing-room. She says her cold may be caused by psychology, and he looks at the book. She says she is getting a raise, and they will be able to get married. She sneezes and says her mother thinks they are already married with five children. Laverne (Veda Ann Borg) comes in and complains her date was broken because of Nathan’s crap game. Nathan says they will get married, and Adelaide sneezes and tells him to get out of her life. He leaves, and she looks in her book and sings “Adelaide’s Lament” about getting a cold.
Sky sings on the street with the Salvation Army and offers his other cheek to Sarah. Nicely-Nicely and Benny tell Nathan that Sarah gave Sky the brush-off. Nathan admits that Adelaide is his weakness, and he sings “Guys and Dolls” with Benny and Nicely-Nicely. Sarah tells Arvide that they shook off the “prince of darkness.” At the mission they find General Cartwright (Kathryn Givney), who says national has decided to close this branch of the mission. Sky knocks and comes in to protest closing the mission. Sky asks the General to give Sister Sarah 36 hours because of a big meeting at midnight tomorrow. Sky shows Sarah his marker, and she guarantees one dozen genuine sinners.
Gamblers are wearing a red carnation. Nathan comes in and says he is waiting for the $1,000 from Sky. Harry the Horse introduces Big Jule (B. S. Pully) to Nathan, who sees he has a gun. Lt. Brannigan comes in and notices so many senior delinquents, and he asks Nathan why they are there. Adelaide and Laverne come in, and Benny says it is a bachelor dinner because Nathan is getting married. Lt. Brannigan and Harry the Horse suggest that they elope. Nathan agrees and sings “Adelaide” with the other men. Nicely-Nicely comes in with news for Nathan, who realizes that Sky and Sarah are gone.
Sky and Sarah visit a church in Havana, and she reads from the guidebook. Sky asks her about the moonlight and the music. He says she could be a missionary without love. She asks for milk, and he orders dulce de leche that has rum in it. She likes it because it is sweet, and he gives her his. He notices her nervous habit of unbuttoning her dress. She gets drunk and notices the song. She asks him how to live. She asks why he is unhappy and says she will make it up to him. She offers him personal help, day and night. She wants to be with him, and they kiss. He buttons her dress and says it is time for dinner. They eat and watch the Latin dancers. Sky begins dancing with one, and so does Sarah. She pushes away his partner and dances with him, starting a fight. They both slug several people. Sky picks up Sarah and carries her out as the police arrive. She puts her head in a fountain and says she heard a bell. She sings “If I Were a Bell” without inhibitions. He kisses her, and she kisses him back. He says they have to catch the last plane back to New York. He admits he brought her there to win a bet, and she calls him a chump.
They return in a taxi just before dawn and walk to the mission. He hands her a flower, and she offers him coffee. He says the tune she is humming has words, and he sings “My Time of Day” about the eyes of a woman in love. She sings it with him. They kiss, and Arvide and General Cartwright come back from their crusade. Sirens are heard, and Nicely-Nicely alerts the gamblers to leave the mission. Lt. Brannigan arrives and says they were tipped off. He asks Sarah to explain why the mission was left open. He calls Sky a decoy. Sky asks her if he had anything to do with that. Sarah says she is a daytime, mission doll.
At the Hotbox Sky sits with Nicely-Nicely, who says he has a message from Nathan for Adelaide. On stage Adelaide and her Debutantes sing “Take Back Your Mink.” Nicely-Nicely says Nathan is not going to elope that night. Sky says he will deliver the message and that he is leaving town. Sky in her dressing-room tells Adelaide that Nathan could not make it. Sky advises her not to fall in love with gamblers. She says it may happen to him.
In the mission Arvide tells Sarah that Sky had nothing to do with it. He sees she is in love with him, but she says she will get over it. Sky opens the door and says she has his marker for twelve sinners that night. She says no thanks, but Arvide tells Sky to make his marker good or he will call him a welcher.
Nicely-Nicely takes Sky underground to the crap game in the sewer. Big Jule says he is out of cash but will now shoot craps against Nathan on credit with his blank dice for $1,000, then for $2,000. Jule wins again for $3,000. Nathan asks to roll with his dice for his marker. Sky and Nicely-Nicely come in. Big Jule objects to the interruption, and Sky knocks him out. Sky asks them to go to the mission, where the air smells better. Nathan says he does not have the $1,000, but Sky says he lost and pays Nathan $1,000. Sky says he will bet $1,000 to each for their souls to come to the meeting. Sky sings “Luck Be a Lady” and puts his money down and rolls the dice.
Harry the Horse insists that Big Jule go to the prayer meeting. Nathan runs into Adelaide and tries to explain. She cries, and he promises they will get married. Nathan is reminded he has to go to the prayer meeting. She calls it a lie and sings “Sue Me” with him.
At the mission General Cartwright says it is past midnight. Sarah says she failed, but then Sky brings in more than a dozen gamblers. Sky tells them to do as they’re told. Sky appoints Nathan his deputy, hands him their markers, and leaves. Arvide introduces General Cartwright, who asks them to give testimony. Nathan orders Benny to confess. Nathan asks Big Jule to repent; he says he has 33 arrests and no convictions. Harry the Horse says Sky rolled them for $1,000 against their souls. Sarah explains it is gambling. Lt. Brannigan comes in, and Nicely-Nicely sings “Sit Down You’re Rockin’ the Boat.” Nathan asks Lt. Brannigan if he wants to testify, and he accuses them of running a crap game there last night. Sarah says he is mistaken. Nathan thanks her and says no one at the mission knew about it. Nathan also says he won the bet with Sky about taking the doll to Havana. Sarah goes out and looks for Sky.
Two wedding cakes head a parade down the street. Nicely-Nicely in uniform with the Salvation Army accepts them. Gamblers march in, followed by the HotBox women, Sky, and Nathan. Lt. Brannigan escorts Adelaide, and Arvide escorts Sarah. In the street Arvide marries Sarah to Sky and Adelaide to Nathan. General Cartwright catches a bouquet and turns to Nicely-Nicely. They all sing “Guys and Dolls.”
This musical comedy depicts the underworld of gambling and the difficulties it can cause in people’s personal lives. That life-style is contrasted to the strict ethics of the Salvation Army that endeavors to reform people.