Spell Bound is the third book in the Hex Hall series. Since there is no cliff hanger this time I assume it's the last. I hope not though. They were all great books.
Sophie is back, but her powers have been locked. Considering she's still in a fight for her life, and maybe the whole world, that's not a good thing. And just when she thought her parents were half normal she finds out about her Mom. There's a shocker. Keep wondering who lives and who dies this time. You'll be surprised. Good ending to the series. Very highly recommended.