Act I

After a hard day's work, mill girls joyously meet their friends at an amusement park (Prologue: The Carousel Waltz). Among them are Carrie, Julie and Penny, who infuriate Mrs. Mullin, the carousel owner, by arousing the interest of her barker, Billy. In the ensuing quarrel, Billy is fired. The girls think that Julie is attracted to Billy (You're a Queer One, Julie Jordan) and Carrie fittingly chooses this as the moment to reveal that she, too, has a beau (Mister Snow). Billy returns, chases Carrie off, and romances Julie (If I Loved You).

Two months later, we find Julie and Billy married and living with Julie's cousin Nettie. Preparing for that evening's clambake, the girls and boys indulge in a bit of gender scuffling, then, with Nettie presiding, celebrate that joyful liberation of spring (Give it to 'em good, Katie/June is Bustin' Out All Over). Julie confides her marital problems to Carrie: Billy is out of work and angry. He has even hit Julie. Carrie's news is happier - Mister Snow and she are engaged. The eavesdropping girls are thrilled, not least when Snow himself shows up (Mr. Snow reprise). Snow and Carrie look forward to married life, a big family and a thriving business in canned sardines (When the Children are Asleep).

Whalers pile unto the waterfront (Blow High, Blow Low). One whaler, the infinitely sleazy Jigger, a friend of Billy's, tries to interest him in committing a robbery, which they can pull off during the clambake. Billy is leery - but then Julie tells him she is expecting a baby. Overjoyed at the thought of fatherhood (Soliloquy), Billy decides to turn thief with Jigger after all. Nettie, Billy and Julie, Carrie and Mister Snow, Jigger, and the rest of the gang sail off to the clambake.

Act II

That evening, resting up after the cookout (A Real Nice Clambake), everyone prepares for the annual treasure hunt. Jigger gets Carrie into a compromising position just as Mister Snow appears. Now the gender scuffling turns serious, as Snow walks out on Carrie. Billy heads off with Jigger for their robbery despite Julie's protests. The women lament their lack of power (Geraniums in the Winder/Stonecutters Cut It On Stone/What's the Use of Wond'rin').

Back on the mainland, Billy and Jigger await the arrival of their intended victim by playing the card game Twenty-One. Jigger, dealing, cheats Billy out of virtually all his share of the coming booty. But the robbery is foiled, Jigger escapes, and Billy, seeing his whole life as a failure, kills himself crying "Julie!" The clambakers arrive and Julie is just in time to trade a few words with Billy before he dies. She tells him, "I love you," after he has died. Nettie and Katy comfort her (You'll Never Walk Alone).

It's not over yet. A Heavenly Friend shows up to take Billy "Up There," where an austere Starkeeper allows Billy to go back and resolve problems he left "Down There." His daughter, Louise, is now sixteen and as excitable and resentful as Billy was. Louise is suffering from the taunts of the Snow children (Snow Children Ballet). Billy takes a star to give Louise as a present. Back on earth with the Heavenly Friend, Billy tries to give Louise the star. She suspiciously resists, and once again, in his inarticulate rage, Billy fails to express his true feelings to those he loves (If I Loved You reprise).

Common sense may tell you that the endin' will be sad - but at Louise's high-school graduation, Billy reassures his daughter and tells Julie "I loved you" (You'll Never Walk Alone reprise).