it's what the title says

Unaware she's been bound from using magic, Frey leads a small, miserable life in the village where she's sent after the death of her mother. But a tiny spark starts a fury of changes and she finds herself running from everything she's ever known. Hunted by council for practicing dark magic, she is certain she's been wrongfully accused. She flees, and is forced to rely on strangers for protection. But the farther she strays from home, the more her magic and forgotten memories return and she begins to suspect all is not as it seems.

1806, England - When Katherine Wentworth, trained killer known as the Silver Sword, is called to the service of Princess Caroline in London she is apprehensive. Years of training and foreign missions means she has had little experience of society and when she is thrown into the bustling London society of balls and card games in the guise of a lady-in-waiting, she is out of her depth. Adding to her troubles is the charming Mr James Willoughby, who seems to spot Katherine even when she thinks she is hidden. But these are dark times. The assassins are getting closer and enemies are everywhere. Any mistake could cost the life of the Princess. And Katherine will not let that happen.

Upon his death, the king had dictated that the queen would rule until she remarried, but her refusal to do so has the nation of Ethios in turmoil. Greedy for power and her cruelty knowing no limits, the queen has even reinstated the slave trade long since outlawed by her husband upon his ascension. A glimmer of hope for a suffering nation arises in a small baby. The Royal Sage has procured the late king's bastard son and has stolen him away to the city slums to live with Harren, a man who bravely rescues orphans from slavery. Naming the boy Kyran, Harren takes him in with the promise of one day returning him to his rightful place on the throne. Ten years later, these plans are dashed when Kyran is exposed to the queen. Harren must race to the safety of the Riverlands, who hold no love for the queen, if there is any chance to save his son, and future king. Saving Kyran saves the nation. If the queen is to be dethroned, the boy must claim his Birthright.

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