Act One: A row of storefronts in Park Slope, Brooklyn. In the rain, our hero, Jack Singer, cannot contain his enthusiastic love for Betsy Nolan, his girlfriend of five years whom he plans to make his fiancée (“I Love Betsy”). He arrives at Betsy’s brownstone, and the two head to Tiffany’s to procure an engagement ring. Jack’s anxiety manifests in a flashback to his mother’s deathbed, where she made him swear that he would never get married... or else be cursed (“Never Get Married”). Overcome with fear and anxiety, Jack runs out of Tiffany’s, leaving a devastated Betsy behind.
Back in Park Slope, Jack babbles over his discomfort, assuring Betsy that his mother’s curse is so close to being done. Betsy has heard this all before and is growing understandably more impatient (“Anywhere but Here”). Jack impulsively announces that they will fly to Las Vegas the next morning and get married immediately.
Arriving at the jam-packed casino of the Milano Hotel, Buddy Rocky, a suave nightclub singer, entertains an enthusiastic crowd (“When You Say Vegas”). Tommy Korman, a gambler in his mid-fifties, and his aide-de-camp, Johnny Sandwich, arrive at the casino.
Later, by the pool of the Milano Hotel, Tommy and Johnny reminisce about Tommy’s deceased wife, Donna, who adored sunbathing at this very pool (“Out of the Sun”).
Jack and Betsy arrive at the hotel and casino, and Tommy and Johnny instantly notice the uncanny resemblance that Betsy has to Tommy’s deceased wife. In their suite, Betsy talks Jack into going to the chapel immediately. As she changes her outfit, an invitation arrives, requesting that Jack take part in Tommy’s poker game. Jack takes this opportunity to avoid the marriage at hand (“The Invitation / Forever Starts Tonight”).
While Jack meets the other players in Tommy’s game, a joyous Betsy strolls through the shopping arcade, searching for an actual wedding dress (“Betsy’s Getting Married / The Game”). The heated poker game ended in a crushing loss against Jack, who ended up borrowing – and losing – $58,000 from Tommy. Tommy plays the nice guy and offers Jack a way out of his debt: allow Tommy a weekend alone with Betsy. (“Come to an Agreement”).
A furious Betsy cannot believe this predicament. She agrees to meet Tommy – with Jack – for one drink. Tommy charms Betsy and reveals that he plans to spend their weekend together in Hawaii. Betsy likes this idea, as both a way to escape Vegas and a way to get back at Jack. Terrified of losing Betsy, Jack tries to stop their departure but is unsuccessful (“Do Something”).
Act Two: Betsy is relaxing at Tommy’s luxurious beachfront Hawaiian home, enjoying the escape from the mainland and the relationship struggles that she temporarily left behind. Meanwhile, Jack is trying to get to Betsy (“Hawaii / Waiting for You” sung by Teihutu ). Tommy’s son, Alex, arrives with his wife, Rose, and newborn baby.
Jack finally lands in Hawaii and frantically attempts to reach Betsy while being greeted by the Hawaiian staff and Raymond, head valet(“Ev’ryday Is Happy in Hawaii”). The staff is actually in the employ of Tommy, who cannot relax, knowing that Jack is there. The staff, including a seductive local named Mahi, finds ways to stall Jack’s mission (“Friki-Fraki”).
Tommy and Betsy continue to get to know each other over drinks and begin to dance to the music of some local singers (“You Made the Wait Worthwhile”), while Jack and Mahi head to the Garden of Disappointed Mothers to break the curse.
Back at the beach house, Tommy and Betsy enjoy dessert while Betsy is becoming even more inebriated. Tommy lies and tells Betsy that this "arrangement" was not the result of a $58,000 deficit, but rather only $800. Betsy is enraged and impulsively decides to marry Tommy back in Vegas and move on with her life (“A Little Luck”).
Jack and Mahi arrive at the garden to break the curse, and Jack pleads with his dead mother Bea Singer to lift the hex ("The Garden of Disappointed Mothers”). To do so, he must prove his love and win back Betsy’s heart (“Isn’t That Enough”).
Unfortunately, Tommy and Betsy have already arrived at the airport, where we discover that Alex and Rose were actually con-people, paid by Tommy to act like his son and daughter-in-law. To make matters worse, the flight to Vegas has closed, and Jack must stow away on a flight with a slew of Elvis impersonators and Travel Agents (“Airport Song”).
Betsy begins to question the reality of the situation and seeks solace at the gym. Meanwhile, Jack is onboard the flight with Roy Bacon and the other Elvis Impersonators and learns that they will soon be skydiving over Las Vegas at midnight (“Higher Love”). Tommy tries to rush the ceremony, but Betsy has some concerns (“I’ve Been Thinking”). Tommy rushes the skeptical Betsy to the ceremony and offers her a million dollars in cash to marry him. She is disgusted, and the two are separated by the arrival of the sky-diving Elvii (“Elvii in Flight”). Jack and Betsy reunite, embrace and get married on the spot (“Honeymoon in Vegas / Finale”).