Warriors: The Fourth Series, Book 6: The Battle of the Stars

War between the Clans and the Dark Forest is imminent. Jayfeather has been suspended from his post as medicine cat after being accused by Ashfoot, the former medicine cat of ShadowClan, of murdering her. Jayfeather wants to travel to the Moonpool to speak with StarClan, but Yellowfang stops him along the way. She tells him to focus on finding the fourth cat. Jayfeather tells Dovewing and Lionblaze that the fourth cat, Firestar, has the power to help them defeat the Dark Forest. Instead, he makes Lionblaze and Dovewing doubt their own powers, and they even consider giving up. At the critical moment, the ancient cat Rock brings the Three into the same dream and helps them see the truth.

Mothwing, RiverClan's medicine cat, brings Jayfeather an omen: reeds burning in the rain. Jayfeather understands that he must go to StarClan and find Ashfoot, so she can reveal the truth about her death and save the Clans. After enduring many hardships, he finally reaches StarClan, only to discover that the Dark Forest's influence has divided it with borders, and that it is suffering its first ever bare-leaf season.

Jayfeather clears up the misunderstandings the other three Clans' medicine cats have about him, reunites StarClan and the four Clans, and finds the prophesied fourth cat: Firestar.

At last, war with the Dark Forest begins. The four Clans unite, and warriors from StarClan and the ancient past join the battle. Brokenstar, Hawkfrost, and Tigerstar are killed one after another, dealing a devastating blow to the Dark Forest, which has threatened the Clans for so long. But the four Clans also suffer terrible losses. Hollyleaf and Honeyfern die in battle, and Firestar uses up his final life...