The ancient witch Chloe bound four men, Aegis, and their descendants, to eternal duty protecting Kaereya from invasion. Generations later, only the superstitious believe in witches and Aegis magic.

Devastated by a callous and false suitor, Vesper accepts the clansman Drew Montoren's offer of handfast. Confused and full of self-doubt, dream visions plague Vesper. News of the royal family’s murder and rumors of imminent invasion come to the clansmen, tormenting Vesper with guilt, for this is the vision that haunts her. She swears to follow her visions and use them against the approaching evil.