Tully Harding never got along with her sister, Joliet. She could handle the years of calculated torment and bullying until Joliet finally pushed her to the edge by stealing her boyfriend from right under her nose. Tully played nice for far too long, and she was done with it. Eager to give as much as she gets, Tully sets her sights on Nathan Rondeau, the guy Joliet has been crushing on since the third grade. What starts as a simple plan for payback quickly spirals into uncharted territory. In the midst of Tully's vendetta, Nathan, the happy-go-lucky charmer facing the looming threat of losing his father's financial support for college if he doesn't pull his grades together, takes the initiative. He proposes a daring deal—a fake relationship with the moody valedictorian in exchange for his academic redemption. As Tully and Nathan navigate their unlikely charade, they discover that their little lies have a way of revealing deeper truths.