Erin Hunter's #1 bestselling Warriors series continues with the second book in the Changing Skies arc, as the Clans continue to navigate an ominous prophecy that foreshadows the end of the cats' connection to StarClan. Still healing from an accident that almost killed her, Tawnypelt is eager to share the message she received from StarClan about a "great peril" looming over the clans. But her vision is dismissed by her son and leader, Tigerstar, leaving Tawnypelt with no choice but to take action on her own. Racked with guilt that he caused his father's death, Starlingpaw is determined to atone for his mistake. His chance comes when Tawnypelt warns him of a "two-faced cat" intent on destroying the clans. Believing himself uniquely suited to find this cat and stop them, Starlingpaw seizes on the opportunity to prove that he is an asset, and not a liability, to SkyClan. Moonpaw is settling into her role as a Thunderclan apprentice, even as she continues to grapple with the voice in her head. But the more she tries to ignore the voice, the louder—and angrier—it grows. Meanwhile, Twolegs have set their sights on the Moonpool, preventing the Clans from reaching StarClan. Will the cats find a way to reach their ancestors before all is lost? Multiple Points of View: Follow the intertwined destinies of three cats: a veteran warrior dismissed by her own son, a guilty apprentice seeking atonement, and a young cat haunted by a mysterious voice. A Perilous Quest: With the Clans' connection to StarClan severed by Twolegs at the sacred Moonpool, the cats must find a new way to hear their ancestors before their world is lost to a moonless dark. Coming of Age: As apprentices Starlingpaw and Moonpaw grapple with immense burdens of guilt and identity, they must find the courage to become the warriors their Clans need them to be. A Hidden Enemy: A warning of a "two-faced cat" working to destroy the clans from within forces Tawnypelt and Starlingpaw on a desperate hunt for a traitor who could be hiding in plain sight.