Prey in ThunderClan's territory has gone missing, and
Fireheart believes that
Tigerstar, leader of ShadowClan, is behind it. Meanwhile,
Bluestar is mentally shaken by Tigerstar's betrayal, for she once thought he was a loyal warrior and deputy. Bluestar believes that if
StarClan had been on her side, none of this would have happened. She refuses to believe in StarClan, and declares war with them, shocking her clanmates. Bluestar decides to name Cloudpaw a warrior because he does not believe in StarClan. Two other apprentices, Swiftpaw and Brightpaw, both choose to track down the animals who have been stealing ThunderClan's prey. Unfortunately, the prey-stealers are a pack of deadly dogs. Swiftpaw is killed, and Brightpaw loses half of her face, making her blind in one eye. Bluestar, thinking Brightpaw will die, promotes Brightpaw to the status of a warrior, but names her Lostface. Meanwhile, Graystripe returns to ThunderClan, and his loyalty is questioned among ThunderClan. Clan life returns to normal, but Fireheart is curious about the dogs. He asks Lostface about them, but she only repeats a few words: "Pack, pack, kill, kill." Whitestorm reports to Fireheart that he and his patrol smelled dogs near Snakerocks. Fireheart goes to investigate. He finds a trail of dead
rabbits that lead to the body of Brindleface, the sweet and gentle queen. She had been killed by Tigerstar in order for the dogs to have a taste of cat blood. Fireheart orders a patrol to discard the rabbits. After Brindleface's burial, ThunderClan evacuates to Sunningrocks. Bluestar is still mentally unstable, so it is up to Fireheart to get rid of the dogs. He and the senior warriors come up with a plan to lead the dogs over the edge of the gorge. The plan works; each cat successfully leads the pack closer to the gorge, breaking away from the group once they lead the dogs to a certain spot, where a fresh runner lies in wait so they can lead the dogs to the next point. Fireheart, the last in line, keeps a good distance from the dogs, but, Tigerstar comes from the bushes and pins Fireheart down, allowing the dogs to catch up. When it seems like Fireheart is about to die, Bluestar, now clear of mind, pushes the pack leader off the edge of the gorge, taking her with it. Fireheart leaps down the cliff into the river and dives in to save Bluestar. Fireheart manages to get a hold on her, but is barely able to keep their heads above the water. However, Bluestar's RiverClan children, Stonefur and
Mistyfoot, discover Fireheart struggling in the river, trying to save Bluestar, and help drag the two cats to the bank. There, Bluestar pleads forgiveness to her kits for lying to them about who their parents were. They forgive her, as they had not known their true heritage until then. Bluestar then tells Fireheart that she realized her Clanmates were not all traitors. She also tells him that he is now the leader of ThunderClan. With that, she loses her final life, and her spirit is sent to StarClan. Fireheart is overcome with grief. Mistyfoot asks if she and Stonefur can help carry her back to the ThunderClan camp and sit vigil for her. ==Main characters==