A case of mistaken identity results in unexpected romance when the most popular girl in high school and the biggest loser must come together to win over their crushes.

Echo must deal with the regular dramas of high school, in addition to grappling with the murder of her older sister, Zoë. But when Echo receives a diary from Zoë's boyfriend, she begins to untangle the secret life her sister lived.

Close friends Marcus and Holly begin their freshman year at a tough public high school in Baltimore County, Maryland. When Cassie, a well liked senior at the school, disappears suspiciously, both of their lives change forever. Together, will they find out what happened to Cassie? And after a dramatic confrontation, will any of them ever be the same?