The Dying Flame

Forbidden magic. An oath to serve. A wrong to avenge.
Orla Grimstal has spent her life hiding who she is and what she can do. The use of magic is prohibited in the Seven Isles and those who break the rules are brutally punished.
But when her sister is imprisoned, Orla will stop at nothing to free her. She soon discovers her power runs deeper - and darker - than she had ever imagined.
Drawn into a dangerous world of secrets and intrigue, Orla is sworn to serve a broken King. Then her past and present collide, and Orla must choose between duty and vengeance.
Will her choice be the spark that burns the Seven Isles?
If you like gripping dark fantasy that you just can't put down, you'll love The Dying Flame, the first book in R.L. Sanderson's Darkfall series.