ThunderClan's darkest hour is upon them, as Tigerstar's quest for power plunges all the Clans into the most terrible danger any cat has ever faced. In order to save his Clan and his friends, Fireheart must uncover the meaning of an ominous proclamation from StarClan:
"Four will become two. Lion and tiger will meet in battle, and blood will rule the forest."
The time has come for prophecies to unfold, and for heroes to rise ...
- The Darkest Hour was released on October 5, 2004.
- It was written by author Cherith Baldry.
- The dedication reads "This book is for Vicky Holmes and Matt Haslum, who helped find Fireheart's destiny. Thank you."
- The cat in the square on the cover is Firestar when he sees his reflection as a lion. The main cover could possibly be cats from BloodClan.