A tall, dark-haired, mustachioed man drives across the city of Budapest until he arrives at a multi-story flat. In one of the apartments, the young medical student Anna Parádi sings about her exams and of her wish to find a man, then she tends to Aunt Zsófi, the elderly apartment owner.Suffering from stomach cramps and anxiety, the man gets Anna to let him in and introduces himself as Zsolt Mohai, an artistic storefront decorator whose wedding will be taking place that day. He hopes Anna, a friend of Zsolt's would-be bride Klára Horváth, would call off the wedding for him as he can't bring himself to do so.The two slowly get to know each other and sing songs over various subjects plaguing their minds. Anna is initially reluctant to help and even tells Zsolt to leave, but she slowly becomes endeared by the man's antics and his looks. Zsolt pours his grievances on the girl and the two eventually begin to discuss deeply personal matters, as well as modern trends in parenting.Klára is preparing for the wedding when Anna phones her, but due to a misunderstanding, she can't forward Zsolt's message. Klára is too preoccupied with her own life and reveals that she would rather be a stay-at-home mom to stay away from her stressful medical job. Anna calls her out on this, but Klára gets angry at her, mistakenly believing Anna is jealous of her groom and her free-spirited, outspoken attitude. Klára slams the phone down before Anna could finish her message. Feeling bad about herself, Klára asks one of her guests, the musclebound boxer Nándor Homolya, to drive her to Anna's place and invite her as well.Anna and Zsolt smoke cigarettes and the girl still tries to force the man to muster courage and go to the wedding. Zsolt however would rather stay there and live with Anna, who is a much better fit for him than Klára. Zsolt is especially drawn to Anna's future profession as a nurse, but he proposes they could also work together in his designer business. Anna shares his feelings but rejects him, convinced that deep down he still loves Klára. They can't continue their chat though, as Klára and Nándor arrive. Zsolt hides among Anna's diving gear in the bathroom while Anna lets the guests in.Anna, Klára and Nándor drink bubbly and have an impromptu song and dance number, but Anna still cannot spill the beans on the situation about Zsolt. Nándor heads to the bathroom where he is faced with Zsolt in his diving gear. Nándor attempts to fight the frogman, but Zsolt uses soap bubbles to confuse him and escape. The combination of alcohol and shock causes Nándor to pass out, so Klára is stuck there in the apartment.While Anna and Klára visit Aunt Zsófi, Zsolt sneaks into the main room still wearing the diving gear, accidentally knocks out Nándor again and hides under the table where he overhears the two women. Klára reveals some deeply personal life details, her suicide attempts and that she has had many lovers other than Zsolt, but she still wants to marry him. Anna still can't tell that Zsolt has been with her the whole day and even begins to fear the wedding herself, realizing that she's fallen in love with Zsolt. Anna eventually confronts Klára on her ideas about marriage and commitment during multiple songs. But Klára is steadfast, she promises to make compromises and make Zsolt happy as a husband. The shtick is up, Zsolt reveals himself and the pair reconcile in a song. Putting their differences aside, Zsolt and Klára express their love for each other and head out to the wedding, leaving Anna behind, alone.One year later, after several failed relationships, Anna is still a lonely woman as she walks on the banks of the river Danube among a crowd of lovers. Zsolt pays her another visit, inviting Anna to his child's naming ceremony. The two reminisce and reveal they had both been in love with each other, but they lacked the ability to "pop the bubble" that separates people. Only the social and outspoken Klára seemed to be able to do this.After the naming ceremony that Nándor also attends, Zsolt is trying to enjoy a bubble bath in his home while Klára tends to their newborn. The woman reveals she has second thoughts about her career -- she wants to go back to medical school and be a nurse like Anna. Upon hearing this, Zsolt submerges in a sea of bubbles.Anna meanwhile sits back in her room in Aunt Zsófi's apartment, in her personal bubble, still alone, still waiting.