In the glittering setup of the Pocket Plaza, Polly Pocket and her friends are primed to perform at the grand opening of a brand-new six-star hotel. The weekend-long celebration centers on a spectacular show, while Polly’s new friend from England, her identical cousin Pia Pocket, arrives with dreams of rock stardom and a twin sparkle that promises trouble and excitement in equal measure.
As the cameras prepare to roll, Pia catches the eye of Miss Throckmorton, the chaperone who believes that anything American is improper and insists Pia should stay true to her British roots. The tension between Pia’s ambitions and Miss Throckmorton’s strict code creates an undercurrent of friction that threads through the opening events. Meanwhile, Polly’s father is unexpectedly delayed at an Icelandic airport, leaving Polly to stand in for him and deliver the dedication speech at the hotel’s momentous ceremony.
To prove Miss Throckmorton wrong and reclaim a bit of fearless fun, the girls hatch a plan: they disguise Pia to look like Polly and immerse her in all things American, while the real Polly steps back to observe and learn. The cousins seamlessly swap identities, a ruse that completely fools Miss Throckmorton and stirs the weekend into a swirl of humor, music, and mischief.
But trouble creeps in as Beth, Polly’s jealous rival, grows suspicious of Polly’s sudden change in attitude and behavior. Beth’s suspicions deepen when she encounters the twins and realizes how perfectly identical they are, and she schemes to use the switch to wreck the ceremony that will be broadcast live to a wider audience.
Miss Throckmorton overhears Beth speaking aloud about Pia and Polly’s plan, misinterprets Pia’s compliance as disobedience, and rushes toward Polly, grounding her to her hotel room. With Polly out of action, Pia steps in to perform Polly’s role at the ceremony, while Polly reads Pia’s speech over the phone. The tension escalates as Miss Throckmorton confronts the double, cuts the call, and confronts the mounting chaos.
Yet Pia’s quick thinking saves the day. She improvises a fresh speech that reveals the error of Miss Throckmorton’s assumptions, and the chaperone realizes her mistake, apologizing to Polly for any kidnapping-like panic and making amends with Pia. This breakthrough allows Pia to pursue her dream of performing with the band, with newfound support from Polly and the others.
That evening, the anticipated performance comes together in a joyful crescendo. Polly and the Pockets deliver a polished, lively show, and Pia steps in to join the melody, thanking Polly for gifting her the weekend that helped her believe in her dream. The grand opening closes on a high note, leaving everyone touched by the sense of teamwork, second chances, and the warmth of shared ambitions.
