The girl with the dragon eyes ( middle earth fanfic )

Did you ever wonder what happened before the hobbit? What about why Elves despised the dwarves so much? Well now you can find out. 13 dwarves trudged blindly into the forest making there way to Bree, to the inn of the prancing pony which was to be the meeting place for gandalf. It was getting late when they were ambushed by orcs. They were seriously outnumbered and were getting ready to battle when hooded figure jumped out and killed all the orcs with ease. After being knocked unconscious ( by Fili and Kili) they removed the cloak to find someone unexpected, a dwarf girl no older than kili. What is so important about her that makes Gandalf so worried? And why is middle earth in so much danger?