Rita arrives in hot, humid Puerto Rico from Paterson, New Jersey with a bad attitude. She has been sent to spend the summer with her grandparents as an alternative to a retreat at a convent, where her friend Meli has been sent. Her parents want her out of contact with her racy boyfriend, Johnny Ruiz, and the result is her exile to the island.

Rita has never spent more than two weeks at a time on the island and she has no desire to get better acquainted with it now. She finds her grandparents and their friends annoyingly gregarious and overwhelming; when she tries to calm herself in the car by practicing deep breathing, her grandmother assumes she's having an asthma attack and harangues her with asthma stories. What Rita really wants is to be left alone.

As soon as the family gets back from the airport, Rita goes to her room to nap and withdraw. When she wakes up, her grandfather is outside her window crooning to his distressed rooster. He tells her (accurately) what she has been dreaming, and reports that the rooster has a skewed sense of time. This is Rita's introduction to her grandfather's talents as a spiritualist. Exasperated, Rita gets up and watches telenovelas with her grandmother, ever critical of Mamá Ana's ongoing dialogue with the television characters. Later that evening, Mamá reports that the next day they plan to travel to the seashore, so Papá can cure a young girl in distress. She explains Papá Juan's powers "that allowed him to see into people's hearts and minds through prayers and in dreams." Rita is skeptical.

The next morning Rita's grandparents awaken her before sunrise. At first Rita fakes an asthma attack so she can stay home alone, but Mamá Ana's dramatic response meets with a miraculous recovery. The three of them head for the beachfront home of the family in need of Papá Juan's help. Having slept in the car on the way, Rita cannot help but enjoy herself on the beach with her grandmother while Papá Juan consults with the señora and Angela in their elaborate, pink house. In the course of the day, Rita learns that the young girl in question refuses to eat or communicate with her mother, and the suspected cause is Rita's mother's boyfriend, the source of the mala influencia in the house. Rita is recruited to invite Angela to eat crab on the beach with them, and during the meal Mamá Ana announces that Rita will be having her fifteenth birthday party in two weeks, and Angela must come.

Rita's party is a huge gathering of neighbors, food, and music, and she gets to wear a blue satin cocktail dress with high heels. Angela and her mother come, and Angela reports that Papá Juan's cure was a success; her mother got rid of her boyfriend and Angela looks much healthier. From then on Rita's summer is greatly improved. She spends a good deal of time with Angela at her home by the beach, and they discuss Rita's story about Johnny, joking that he might be suffering from a mala influencia himself. Over time Rita feels disassociated from her experience with Johnny, and it seems like a movie she has seen years ago.

By the time her family arrives in August, Rita feels integrated enough into life on the island to take lessons in perceptiveness from her grandfather, and calls herself a medium. Although at first she plays on her mother's guilty anxiety and holds back from her, she soon warms up and assures her that the summer has gone well. Her mother reports that Meli enjoyed her convent experience so much that she plans to attend parochial school in the fall. Instead of being stricken by the news, Rita laughs, and as Mamá Ana reports on the summer to her mother, Rita fantasizes about how she and Meli can get together to move in on the cute boys at the Catholic school.