Firebrand — Gillian Philip

It is the last decade of the sixteenth century: a time of religious wars in the mortal world. But the Sithe are at peace, hidden behind the Veil that protects their world until their queen, Kate NicNiven, determines to destroy it.

Seth MacGregor is the half-feral son of a Sithe nobleman. When his father is assassinated and Seth is exiled with his brother Conal to the full-mortal world, they vow not only to survive, but to return to reclaim their fortress and save the Veil.

But even the Veil's power cannot protect the brothers when the brutal witch-hunts begin....