Moonshadow by Thea Harrison

Her past is a blank, her future uncertain….
Recovering from a shooting, LAPD witch consultant Sophie Ross leaves her job and travels to the U.K. to search for answers about her childhood. When she encounters a Daoine Sidhe knight of the Dark Court, she becomes entangled in an ancient hatred between two arcane forces.

He has given his body and soul to fight for his people….
Barred from his homeland along with his surviving brother knights, Nikolas Sevigny is embroiled in a conflict that threatens everything he holds dear. Only by uniting his people’s resources can they hope to prevail against Isabeau, the deadly Queen of the Light Court. He will do anything and use anyone to return home to Lyonesse.

When Nikolas encounters Sophie, he sees a tool to be used. The insouciant witch might be the key to unlocking every passageway that has been barred to the knights of the Dark Court, even as a fascination for her takes root in what’s left of his soul. Sophie has no intention of becoming anyone’s pawn, yet the fierce Nikolas is so compelling, she can’t deny the temptation that endangers her guarded heart.

As magic threatens Lyonesse, Queen Isabeau unleashes her merciless Hounds, and Nikolas and Sophie become embroiled in a race for survival. Meanwhile, the passion that ignites between them burns too hot to be denied and quickly turns into obsession. Thank goodness they both know better than to fall in love…