The end of the stars draws near. Three must become four to battle the darkness that lasts forever...

After countless moons of treachery, Tigerstar's Dark Forest apprentices are ready to lay siege upon the warrior Clans. As Jayfeather, Dovewing, and Lionblaze prepare to lead their Clanmates into battle, they await the arrival of the mysterious fourth warrior who is prophesied to help lead the Clans to glory.

The darkest hour the Clans have ever faced has dawned. Hopes will be shattered and heroes will rise as the warriors fight for their very survival.

When kittypet Tiny crosses paths with some wild forest cats defending their territory, he is left with scars—and a bitter, deep-seated grudge. As his reputation grows among the strays and loners that live in the dirty brick alleyways of Twolegplace, he changes his name to Scourge and puts everything about his old life behind him—except his deadly desire for revenge.