What if Anna and Elsa never knew each other?As the future queen of Arendelle, Princess Elsa leads a life full of expectations and responsibilities-not to mention questions. What type of ruler will she be? When will she have to pick a suitor? And why has she always harbored the feeling that some critical piece of her is missing?Following the unexpected death of her parents, Elsa is forced to answer those questions sooner than she'd hoped, becoming the sole ruler of her kingdom and growing lonelier than ever. But when mysterious powers begin to reveal themselves, Elsa starts to remember fragments of her childhood that seem to have been erased-fragments that include a familiar-looking girl. Determined to fill the void she has always felt, Elsa must take a harrowing journey across her icy kingdom to undo a terrible curse ... and find the missing princess of Arendelle.