Take the Key & Lock Her Up (Embassy Row #3)

Centuries ago, the royal family of Adria was killed... or so everyone thought. Now Grace Blakely knows the truth: there
was one survivor, and that survivor's blood runs through her veins.
This simple fact could cause a revolution-which is why some people
will stop at nothing to keep it from coming to light. There is
only one way for Grace to save herself, save her family, and save the
boy she loves. She must outmanoeuvre her foes, cut through the web of
lies that has surrounded her for years, and go back to the source of all
her troubles, despite the risk. If she wins, she will inherit a
throne. And if she loses, she will inherit the fate of all the dead
princesses who came before her.