Some of the ponies of Equestria end up in the warrior cats forest as cats. They must now learn from Starclan the ways of the warrior cats and form their own clan.

A spell miscast and random chances leaves Twilight in dead confusion, as suddenly she, her friends, the Crusaders, the Princesses, and Derpy Hooves get turned into cats. They find themselves in the forest where the four Clans live, and must learn the warrior code to defeat the real cause of the change in events.

This story takes place after "The Last Hope" in the Warrior Cats series. Possible spoilers of the books.