Royal Blood by Aimée Carter

Royalty, murder and scandal combine in this thrilling new series about an American girl who becomes the British Monarchy's greatest nightmare.
As the King of England's illegitimate daughter, 17-year-old Evan Bright knows a thing or two about keeping secrets. 

But when she's forced to spend the summer in London with her father and the royal family, who aren't exactly thrilled she exists, her identity is mysteriously revealed, and suddenly the world is dying to know every juicy lie the press prints about her. 

After a fun night turns deadly and Evan becomes the primary suspect in a murder investigation, the escalating rumors and fallout threaten to tear her life apart. As she fights to uncover the truth about what happened, she discovers royal secrets that are even more scandalous than she imagined – secrets that could change the monarchy forever.

And her own may be next.