Shy, nerdy Tanvi has always thought of her perfect cousin Mimi as her sister. Not only did Mimi's family raise Tanvi after the tragic death of her parents, fierce Mimi has always protected Tanvi at school. At least until Mimi fell under the spell of their flawless, rich classmate, Beth . . . Tanvi's biggest bully. Fearing another terrible year, Tanvi decides to take a desperate, preemptive strike--and captures an incriminating photo of Mimi and Beth at a party. When Tanvi wakes up the next day with a bump on her head, scratches on her leg, and no memory of what caused her injuries, Mimi is gone.

Tanvi begins to fill the gaps in her memory and question Mimi's friends and enemies, hoping to bring her cousin home. But when new evidence comes to light, the search for Mimi takes a dark turn as the cops announce that they are now hunting a murderer. Could Tanvi be the killer?

To save her family, Tanvi must revisit the worst night of her life and the darkest parts of her past to discover if she's capable of murder--and the truth of what happened to Mimi.