Nineteen-year-old Ruby Kilstrong gets to attend Diamond City's most prestigious college, study history, eat pizza, and play fastball in her free time-which she is not so great at. On top of that, she gets to live at the palace with Allseer Louis Kilstrong like royalty. The only downside is she can't remember her life past the last year.

Unfortunately for Ruby, amnesia is the least of her worries when a notorious gang called the Scarfaces launches an attack on her city. She is forced to escape with classmates who claim there is more to Ruby than meets the eye. Not only does she know her way around a sword, but she bears a striking resemblance to the legendary Sage Arpine, who united Diamond City's four districts many years ago. In the escape, Ruby meets one of Sage's nephews and learns that the likeness might not be a coincidence after all.

Regardless of her past, Ruby has survivors to defend and an abandoned town to secure. With the help of some age-old allies, Ruby learns to fight and toughen up in the face of the deadly Scarfaces. Becoming the hero is no easy feat, though, and she is nowhere near the warrior Sage used to be.

Before all goes to hell, Ruby can run away and start a new life. But does she really want to ignore the role Louis played in her amnesia and the husband and twin sons who have been waiting for Sage to wake up from her hibernation?

It'd be the easy way out.