During a layover at LAX, fifteen-year-old Flynn Barlow, her older stepbrother Amos Abernathy, and their nine-year-old half-sister Poppy decide to ditch their family Christmas vacation in Bora Bora, where their parents plan to announce their divorce, and the three siblings instead spend three days in Los Angeles, hooking up with Flynn's summer camp crush, visiting Disneyland, reuniting with Amos's father, and confronting the simmering romance between Flynn and Amos.