Act I
At a glittering art deco nightclub in 1933, Sweet Sue McGinty welcomes a high-spirited crowd to Chicago’s hottest speakeasy (“What Are You Thirsty For?”). After the Feds raid the club, Sue decides to leave Chicago and head west with an all-girl band.
Meanwhile, two of the club’s musicians – saxophonist Joe, a charming ladies’ man, and bass-playing Jerry, his levelheaded best friend – head to the Cheetah Club to look for a new gig. The club manager refuses to hire Jerry, who is Black, but Jerry and Joe, calling themselves the Tip Tap Twins, insist that “You Can't Have Me (“If You Don't Have Him”).” Fortunately, the club’s owner, a powerful gangster named Spats Colombo, takes a shine to the duo and hires them to perform that evening.
After their successful debut, Jerry and Joe enter Spat’s office to request better billing – just in time to witness Spats and his gunmen murdering Toothpick Charlie and his goons. With Spats in pursuit, Jerry and Joe escape into the chorus girls’ dressing room, where Joe comes up with a plan: They’ll disguise themselves as women, join Sue’s all-girl band, head west to San Diego and escape to Mexico (“Vamp!”).
The next morning at the train station, Joe and Jerry, now Josephine and Daphne, finagle their way into joining Sweet Sue and Her Society Syncopators (“I'm California Bound”).
On the train, Joe falls for the band’s beautiful lead singer, Sugar Kane, who admits to Josephine that saxophone players get her motor purring (“A Darker Shade of Blue”).
As the Syncopators cross the country playing gigs, Sugar, Josephine and Daphne “Take It Up a Step” by adding a new act: a dance routine featuring the three of them as The Tip Tap Trio.
Joe, who struggles to pass as Josephine, marvels at Jerry’s ease in becoming a woman. Jerry, feeling more and more empowered as Daphne, schools a greedy bar manager (“Zee Bap”).
Sugar and Josephine grow closer, and Sugar shares her childhood dreams of movie stardom (“At the Old Majestic Nickel Matinee”).
Arriving in San Diego, the band checks into the glamorous Hotel Coronado. The hotel’s owner, the charmingly eccentric Osgood Fielding III, falls instantly for Daphne (“Poor Little Millionaire”).
Joe, dressed as a man, heads off to escape but bumps into Sugar. Flustered, he impersonates Kip Von Der Plotz, Hollywood screenwriter. Sugar is smitten.
That night, Sue and the Syncopators – minus saxophonist Josephine – play the hotel ballroom. Osgood and Joe/Kip sit in the audience, admiring Daphne and Sugar. Meanwhile, Spats and his goons, trailed by Federal Agent Mulligan, arrive in pursuit of Joe and Jerry (“Some Like It Hot”).
Act II
Later, in their hotel room, Josephine claims to have missed the show due to food poisoning. Osgood invites Daphne and the girls to join him for some late-night dancing in Mexico (“Let’s Be Bad”).
Sugar and Kip share a romantic evening, fantasizing about the movie they’d make together (“Dance the World Away”).
At a beautiful moonlit cantina in Mexico, Osgood tells Daphne that he was born Pedro Francisco Alvarez, and he has always been two people at once. Recognizing Daphne’s uniqueness, he asks her to marry him (“Fly, Mariposa, Fly”).
The next morning, back in San Diego, Daphne tells Jerry that she has discovered herself: she is both Daphne and Jerry, and she’s engaged (“You Coulda Knocked Me Over with a Feather”). Daphne tells Joe it’s time for him to be honest with himself, too. At rehearsal, Joe battles his conscience and finally decides to tell Sugar the truth (“He Lied When He Said Hello”).
Before the show, Osgood stops by the dressing room to drop off a note and gift necklace for Daphne. Sue introduces the girls to their new investor: Spats Colombo. After the others leave, Sue catches Joe without his wig, and, deducing the truth, tells Joe and Jerry to play this one last show before making a quick exit to Mexico.
Joe realizes he’ll have to say goodbye to Sugar. Giving her the necklace Osgood left for Daphne, Joe reads the note, pretending it’s a farewell from Kip. Devastated, Sugar puts her heart and soul into that night’s performance (“Ride Out the Storm”).
On stage, Joe removes his Josephine wig and starts to tell Sugar the truth. Sugar slaps him, but Spats rises with a gun in his hand, setting off a wild chase. Spats and his goons pursue Joe and Daphne, Agent Mulligan trails Spats, and Sue, the Syncopators and the hotel staff add to the mayhem (“Tip Tap Trouble”). In the end, Mulligan catches Spats and his henchmen. Joe steps up as a witness to Toothpick Charlie’s murder, and the goons corroborate his story. Joe apologizes to Sugar, who cautiously forgives him, and Osgood offers to finance the band. Before Daphne can explain herself, Osgood says he understands, and he thinks she’s perfect.
Months later, at Daphnecita’s, the hottest new nightclub in Los Angeles, Sweet Sue, the Syncopators and the happy couples celebrate the end of Prohibition (“Baby, Let’s Get Good”).