Devious Magic (Book 3, Stella Mayweather Series)

Witch hunters who will stop at nothing.
A deadly foe who wants to harness witches' power.
A secret supernatural world that is on the verge of revealing itself.
When the recent surge of supernatural activity in the secretive town of Wilding apparently draws the fearsome Brotherhood, Stella knows she could be risking her life to give in to their demand to return to England.
But defying them sees her world fall apart as her best friend is kidnapped. Lured home to her birthplace, Stella's powers are tested to the limit as she battles magic and trickery at the heart of the Brotherhood's operations. But flight across the world brings as many questions as it does answers, and Stella can never be sure who is on her side and who will betray her.