Grail — Stephen R. Lawhead

Drought, plague, and war have left the Isle of the Mighty battered and its heart, the beloved Arthur, grievously injured--until a secret relic is brought before the dying King; a Holy Grail that heals his wounds and restores his vigor.

But soon evil enters the royal court in the guise of a beautiful maiden; a soulless, malevolent force capable of seducing the King's loyal champion, confounding the sage whom some call Merlin, and carrying the sacred Grail--and Arthur's adored Queen--off into the dark unknown.

And now Arthur faces the greatest challenge of his sovereignty: a quest of recovery that must lead the noble liege through realms of magic and the undead, on a trail that winds inexorably toward a grim confrontation with his most foul nemesis...and his destiny.