Lifelong best friends Lena Kaligaris, Tibby Rollins, Carmen Lowell, and Bridget Vreeland are teens from
Bethesda, Maryland who are about to spend their first summer apart. Lena is visiting her grandparents in
Santorini, Greece; Bridget is attending soccer camp in
Baja California, Mexico; Carmen is visiting her father in
South Carolina; and Tibby is staying home. While shopping together, they find a pair of jeans that inexplicably fit them all perfectly. They decide to share them equally over the summer, before parting the next day. While wearing the Pants, Lena is saved from drowning by local Greek boy Kostas Dounas. She later discovers their families are enemies. When Lena returns the shirt Kostas loaned her, he explains the dispute was over money and fish. Their grandfathers simultaneously claim that the other one cheated them. Kostas pursues Lena, insisting the feud has nothing to do with them. She initially rebuffs his advances but eventually they secretly date. Just after Kostas tells Lena he loves her, her family drags her away before she can answer. Lena's grandmother berates her for seeing him, and for sketching him shirtless. Lena appeals to her grandfather, and he lets her see Kostas before he leaves for
Athens. Working at a department store, Tibby finds young girl Bailey Graffman unconscious, so calls
911. Later, Bailey delivers the pants to Tibby's home when they are erroneously delivered to hers. Fascinated by Tibby's film-making, Bailey appoints herself her assistant. Initially annoyed, Tibby later accepts Bailey, and learns she has
leukemia. When Bailey again goes into hospital, Tibby initially avoids her, but eventually visits with the pants. Tibby pleads with Bailey to take the pants and let the magic help her, but Bailey insists their magic brought them together. After spending time together there, Bailey dies. Devastated, Tibby then edits her film inspired by and called “Bailey.” Arriving in South Carolina, Carmen finds her white father Al about to marry Lydia, mother of teens Paul and Krista. They are all blonde
WASPs, unlike Carmen, who is a
Catholic Puerto Rican. Although Carmen's father and step-family initially seem welcoming, they emotionally exclude her, acting as if she is not there. When Carmen comes downstairs speaking Spanish, assuming her father still understands her from his marriage to her mother, she is told that nobody does. Her idea of making dinner with Puerto Rican recipes does not interest them either. Carmen overhears Krista and her friend talk mockingly about her. Uncomfortable that her father refers to Paul and Krista as his kids, Carmen resents his being an enthusiastic and present father to them, while he has been largely absent from her life. She is embarrassed at a dress shop when her bridesmaid dress is much too small. Angered when the saleswoman calls her "the other one", Carmen shouts at everyone and runs away. Carmen eventually returns home and sees Al and her step-family happily enjoying dinner together, oblivious of her absence. Enraged, she throws a rock at their dining room window, cracking the glass, and returns to Maryland. Tibby tries to help Carmen with her feelings toward her father, but Carmen lashes out at her. Tibby leaves upset, although they eventually reconcile. Tibby convinces Carmen to confront her father by phone, during which she expresses her feelings of neglect and abandonment. He apologizes sincerely, but Carmen says it is not enough. At soccer camp, Bridget develops a crush on coach Eric Richman; despite relationships between coaches and campers being forbidden, she flirts with him and seeks his attention during games. When it is Bridget's turn with the Pants, she seduces Eric on the beach at night, losing her virginity. Bridget becomes depressed, disappointed it made her feel empty. She isolates herself when returning home, but when Lena finds her note, she sends Carmen and Tibby to Bridget's. Bridget fears she might be like her mother, whose depression lead to her suicide. They reassure her that she is stronger than her mother, comforting her with happy memories. On his way back to
Columbia University, Eric apologizes to Bridget for his behavior and hopes she will consider him when she is older. The girls meet Lena at the airport, driving to South Carolina to attend Carmen's father's wedding, despite her reluctance. He publicly apologizes for neglecting her, Carmen accepts his apology, joining the blended family onstage for the ceremony. ==Cast==