Poderia ser The Spell Sword por Marion Zimmer Bradley, parte da série Darkover , (detalhes abaixo) ou sua sequela A Torre Proibida .
Callista, a Keeper at Arilinn Tower, has been abducted and confined so that she cannot reach even her twin sister Ellemir telepathically. The only person she can reach is a Terran, Andrew Carr, who has no idea what is going on. His search for his "ghost-girl" crash-lands him in the mountains, an experience he barely survives.
Meanwhile Ellemir has sent for her kinsman, Damon Ridenow, a sorcerer trained at Arilinn, to find and rescue Callista. Damon, however is no swordsman; the person for that job would be the girls' father, who has just been crippled by a Cat-men attack. All three men are needed to rescue Callista, and they will need to harness the magic of the spell sword to succeed.