Into Thin Air:

A twelfth-century warrior-turned-Guardian Knight, Gawan of Conwyk is about to finally become mortal. But then he finds a beautiful woman by the side of the road near Castle Grimm-she is his soulmate, and it's up to him to save her life.

Ellie doesn't remember who she is or how she got to the north of England. Together they set out to solve the mystery of her almostdeath, but neither Ellie nor Gawan is prepared for the soul-searing passion they discover...