The second book in a new series from blockbuster Warriors author Erin Hunter about two orphaned cat sisters who discover a secret world of magical creatures . and the humans who are out to control them. Willow and Luna have always relied on each other to survive in the city. But when the sisters stumbled on a hidden world of magical animals and human witches, they realized they were no ordinary cats. They have magic themselves. Now, for the first time, they must forge their own paths. Willow is on the run with Violet, a witch girl with whom she shares a powerful bond. But Violet's parents, the Rousseaus, are determined to hunt them down and destroy Willow.

Meanwhile Luna is reeling from a deadly attack by the same Rousseaus. She and her fellow Renegades are driven to join forces with the Truthtellers, a sinister coven of animals with secrets of their own. As tensions explode into magical conflict, Willow and Luna must grapple with the same question. What if your worst enemy is your own sister?.