The spellbook is a book recovered from a cell in the prison level; among its contents stand the spells Disguise Self, Shield, Magic Missile, and Silent Image.
It was found amidst the skeletons of an elven woman and a human man, together with a note and two healing potions. The note told that the two had been lovers in Justinian's day, and that the man had laboured at a spell to save the elf from an unnatural physiology.