Violet Paz, a Chicago high school student, reluctantly prepares for her upcoming "quince," a Spanish nickname for the celebration of an Hispanic girl's fifteenth birthday.

"Every year, summer begins when the Callahans arrive on Mariposa Island. That's when Elena Finney gets to escape her unstable, controlling mother by babysitting for their two children. And the summer of 1986 promises to be extra special when she meets J.C., the new boy in town, whose kisses make Elena feel like she's been transported to a new world. Joaquin Finney can't imagine why anyone would want to come to Mariposa Island. He just graduated from...

In the summer before eighth grade, Marco Suarez kissed his best friend Sally Blake. This was his first spark. And since then, whenever he's thought about that moment, he's traveled through a wormhole-of sorts-to relive those brief seconds when time sped up (or, rather, his view of time distorted) and he kissed her. And then, at the end of that year, she disappeared, leaving in that way that people sometimes leave-alive and well and somewhere out there...