Act One

Mille Dillmount arrives in 1922 Manhattan. She has guts, pluck, charisma and moxie. She may be from a small town, but she's got big dreams. She's here to make those dreams come true and nothing can deter her or send her running home. She intends to be chic and modern, but she's not quite there yet ("Not for the Life of Me"). In the midst of all the excitement of her arrival, Millie gets mugged. She loses her scarf, hat, shoe and purse. When Jimmy Smith, a brash city slicker with an irrepressibly buoyant personality, enters, Millie trips him to get his attention. He tells her to go back to Kansas and, when Millie refuses, he suggests that she check into the Hotel Priscilla, a rooming house for actresses. The defiant Millie plans on staying and making her mark in the big city just like all the other girls at the Hotel Priscilla ("Not for the Life of Me – Tag").

At the hotel, the girls – Lucille, Rita, Alice, Gloria and Ruth – bemoan not getting any acting roles. Ethel brings in that day's newspaper, featuring a headline that reads, "White Slavery." She tells the girls that many young girls, mostly orphans, have suddenly disappeared without anyone noticing. Mrs. Meers, the hotel's proprietor, enters. She is a former actress-turned-criminal. She pretends to be a kindly Chinese woman in order to mask her true profession: a white slave trader. She thinks she is a wonderful actress, but her Chinese accent is deplorable and her depiction of a hateful stereotype is held up to ridicule by real Chinese people. Mrs. Meers gives Ethel a telegram with the sad news that her great uncle has died; Ethel reveals that she is now an orphan. Mrs. Meers invites her to come have a cup of tea and then stealthily makes arrangements to sell Ethel into slavery.

Millie enters, and Mrs. Meers tells her that she has to leave the hotel because she is behind on rent. While Millie tries to persuade "Meersie" to let her stay, the ingénue, Miss Dorothy Brown, enters. Millie makes a deal with her to share her room as long as Dorothy sleeps on the floor. Miss Dorothy is excited to make the acquaintance of her first poor person; she's on her way down. Conveniently, Millie is on her way up ("How the Other Half Lives"). Millie explains that she plans to marry her boss; the only hitch is that she doesn't have a boss yet. Mrs. Meers offers Ethel's room to Miss Dorothy, which has just recently become available. She is also delighted to discover that Miss Dorothy is an orphan. Millie and Miss Dorothy head upstairs. In order to get the elevator going they must tap dance their way up. They ascend as they chat happily.

In the laundry room of the hotel, Ching Ho and Bun Foo fold towels. Mrs. Meers enters and tells Bun Foo to take Ethel to Buddha – her contact in the white slave trade – and to collect the money. Ching Ho is to take a snack to the new arrival, Miss Dorothy. We discover that the boys, who speak and sing in Chinese with subtitles, are working here to save money to bring their mother over from Hong Kong ("Not for the Life of Me – Reprise").

Later, Millie attempts to interview with Trevor Graydon, the President of Third of Sincere Trust Insurance; Graydon is a businessman who needs a stenographer... and who happens to be single. Miss Flannery, the office manager, is clear that she thinks Millie is a modern and does not approve of her. Mr. Graydon, however, gives Millie a convoluted typing test, which she passes with flying colors ("The Speed Test"). She gets the job.

Back at the hotel, Ching Ho brings Miss Dorothy a room service apple, which Mrs. Meers has injected with a large hypodermic needle. However, when Ching Ho see Miss Dorothy, he is instantly smitten. Rather than give her the apple, he tries to warn her about Mrs. Meers. Mrs. Meers tries to give Miss Dorothy the apple herself, but is foiled by Millie and Alice's sudden appearance. Alone, Mrs. Meers laments the acting career that she was never given the chance to have and applauds herself for putting her talents to such good use in her current line of work ("They Don't Know").

Millie, Miss Dorothy and the girls head out to celebrate Millie's job. They try to find a speakeasy, but to no avail. They bump into Jimmy, who shows them that there is one just under their noses. Millie begrudgingly accepts his help getting them in – since he is a member – and Jimmy is impressed that Millie has stayed in New York. Inside the club, a wild dance ensues that leads Millie and Jimmy to dance together ("The Nutty Cracker Suite"). The joint is then raided. While mug shots are being taken, Jimmy and Millie get to know each other better: he's from Long Island and currently flits from job to job to support his lifestyle. In the jail cell, Jimmy watches Millie sleep and tries to convince himself that he is not falling for her ("What Do I Need with Love"). The next morning, Jimmy tries to invite Millie to a Yankees game. She declines, telling him that her boss is her fiancé. Jimmy insists that they go to the game anyway, since his interest in her is not romantic. He tells her to bring Miss Dorothy, as well.

At the Priscilla, Mrs. Meers enters in a laundry cart, sporting rubber gloves, surgical mask and scrubs, holding a rag and a bottle. She intends to knock Miss Dorothy out and cart her away. She chastises Ching Ho for losing his heart to Miss Dorothy and making her do this. Before she can follow through with her dastardly plan, Millie enters in a new dress to show the girls. Millie asks Mrs. Meers about the bottle. Mrs. Meers claims that the bottle is soy sauce and that she was using it to clean the carpet. Millie and Miss Dorothy go to meet Jimmy, who has gotten them an invitation to a welcome home party for Muzzy Van Hossmere in her glamorous penthouse.

The glamorous Muzzy enters, singing the praises of New York City ("Only in New York"). Muzzy's guests include New York's elite, like the Gershwins and Dorothy Parker. Jimmy enters with Millie and Miss Dorothy, explaining to Millie that his father was the gardener at Muzzy's Long Island estate. Miss Dorothy meets Rodney, an old friend from the orphanage, and she, Jimmy and Rodney leave. Muzzy tells Millie that, although the now-deceased Mr. Van Hossmere was very wealthy, she married him for love before she knew his means. During the dancing, Millie spills champagne on Dorothy Parker's dress. Muzzy tells Jimmy that he is in love with Millie and asks what he is going to do about it.

On the terrace, Jimmy calms Millie down after she has stained Parker's dress with champagne and soy sauce. The conversation turns to Mr. Graydon. They argue over Millie's plan, going nose-to-nose when Jimmy grabs Millie and kisses her passionately. She responds, and Jimmy exits in a panic. Millie realizes that she is in love with Jimmy ("Jimmy"). The stage changes to the Hotel Priscilla, where Millie walks in to catch sight of Jimmy leaving Miss Dorothy's room and asking her not to tell Millie. Shocked and brokenhearted, Millie watches him go.

Act Two

At Sincere Trust, Millie will not pick up the phone to talk to Jimmy. Office manager, Miss Flannery, and the other girls urge her to move on. They all have boys in their life that they need to forget ("Forget about the Boy").

Meanwhile, Millie's attempts to flirt with Graydon fall flat. Jimmy shows up, which only interferes further with her plan. Miss Dorothy's presence reminds Millie of the previous night, but the two ladies make up; Miss Dorothy tells Millie that she was just hit on in her audition. Millie encourages Miss Dorothy to toughen up and become a modern, starting with bobbing her hair. Graydon enters and sees Miss Dorothy. They stare at one another and are smitten ("Ah! Sweet Mystery of Life" / "I'm Falling in Love with Someone"). Graydon asks Miss Dorothy to dinner and begs her not to alter her lovely appearance. 

Elsewhere in the building, Jimmy crawls onto a window ledge in order to avoid Flannery and to get Millie's attention. Millie asks him why he was kissing Miss Dorothy, and he replies that he asked for Miss Dorothy's advice about his feelings for her; Jimmy realizes that he loves Millie ("I Turned a Corner"). The two decide to dine at the Cafe Society that night, where Muzzy will be performing. Millie, Jimmy, Graydon and Miss Dorothy all profess their love while Ching Ho enters and professes his own love for Miss Dorothy ("I'm Falling in Love with Someone – Reprise").

Back at the Hotel Priscilla, Mrs. Meers stalks Miss Dorothy, this time with pesticide spray guns. When Ching Ho balks, Mrs. Meers reminds him that he is trying to get his mother to New York. She brings to mind the memory of Bun Foo and Ching Ho's mother, and they recommit to the job ("Muquin"). That night at the floorshow at Cafe Society, Muzzy performs her number ("Long as I'm Here with You"). Millie and Jimmy listen to her sing from the kitchen, where they are washing dishes. Millie visits Muzzy in her dressing room, where she tells Muzzy that she is crazy about Jimmy, but she doesn't want a lifetime of washing dishes in a restaurant kitchen. Muzzy tells Millie that her plan to marry her boss is flawed because, even though she originally thought Mr. Van Hossmere was poor, she married him for love and never regretted it. Millie realizes that she must follow her heart ("Gimme Gimme"). In another part of Cafe Society a drunken man is singing about a lost love; Millie discovers that it is Graydon. Miss Dorothy has stood him up. He even went to the hotel, but she had already checked out. Jimmy overhears and is convinced that something is very wrong. Millie realizes that two orphan girls disappeared without a word to anyone but Mrs. Meers. The three of them decide that they need a decoy orphan, and Millie knows someone who will help them.

Muzzy enters the Hotel Priscilla, disguised as an ingénue, wearing a blond wig and carrying a beat up suitcase. Although Mrs. Meers thinks that the new girl is a little long in the tooth to be an orphan, she welcomes her to the hotel and offers her some green tea. Meanwhile, upstairs, Ching Ho vows to help the gagged and bound Miss Dorothy. Mrs. Meers finally recognizes Muzzy, and Muzzy realizes that Mrs. Meers is Daisy Crumple, who was kicked out of the chorus when they were younger. Mrs. Meers reveals her new profession. Millie, who is hiding in another laundry cart, transcribes the entire conversation ("The Speed Test – Reprise"). Mrs. Meers demands proof, and Bun Foo says that he speaks English and will testify against her. While they search for Miss Dorothy, Mrs. Meers escapes. Miss Dorothy is discovered in an embrace with Ching Ho, who has rescued her from an unspeakable fate ("Ah! Sweet Mystery – Reprise"). The boarders at the hotel, armed with pesticide cans of their own, find Mrs. Meers and force her to follow them to the police station.

Jimmy proposes to Millie and, even though he is poor, she accepts. After she agrees to marry Jimmy, she finds out that he is actually Muzzy's stepson, Herbert J. Van Hossmere, the Third. Miss Dorothy also turns out to be Jimmy's sister, Dorothy Carnegie Mellon Vanderbilt Van Hossmere. Muzzy, afraid of fortune hunters and James squandering his money on the wrong kind of women, sent the children out with 25 dollars and the hopes that they would come back with proper sweet partners, which they did. Bun Foo acquires a job as Graydon's stenographer and he and Ching Ho greet their mama in a joyous family reunion ("Finale").