The last time Jacob Reckless entered Mirrorland, he traded his life to save his brother from becoming a Goyl. Now bearing his brother's fairy curse, Jacob has one year to live unless he can find a way to expel the deadly moth from his chest. After months of fruitless searching, Jacob journeys through his father's mirror one last time to deliver the bad news to Fox. But there they hear of an enchanted crossbow, which was known to strike down any army it faced, and less well known for its healing power when shot by a loved one..