October Daye series - Hugo Award-winning author Seanan McGuire - "Top of my urban-paranormal series list!" --Felicia Day
It's been almost a year since October "Toby" Daye averted a war, gave up a county, and suffered personal losses that have left her wishing for a good day's sleep. She's tried to focus on her responsibilities, but she can't help feeling like her world is crumbling around her, and her increasingly reckless behavior is beginning to worry even her staunchest supporters.
To make matters worse, Toby's just been asked to find another missing child...only this time it's the changeling daughter of her fellow knight, Etienne. Chelsea, a teleporter like her father, is the kind of changeling the old stories warn about: the ones with all the strength and none of the control. She's opening doors that were never meant to be opened, releasing dangers that were sealed away centuries before--and there's a good chance she could destroy Faerie if she isn't stopped.
Now Toby must find Chelsea before time runs out, racing against an unknown deadline and through unknown worlds as she and her allies try to avert disaster. Toby thought the last year was bad. She has no idea.