The Devil's Door — Sharan Newman

1140 Anno Domini:
A wealthy countess lies dying at the Convent of the Paraclete, brutally beaten by unknown assailants. Despite entreaties, she is unwilling to name her killer. Beautiful Catherine LeVendeur, the Paraclete's most learned young novice-scholar, vows to find out the identity of the woman's attacker.

But Catherine is torn between her quest for justice and the pledge made to her beloved Edgar, who has come to lead her from the convent to a life of the flesh. If Catherine abandons her crusade for the truth, others will die.

And the convent that she loves might be destroyed.