In the fog-choked town of Grayhaven, strange symbols begin appearing on students' skin-granting power, luck, and terrifying gifts. Sixteen-year-old Rowan Hale soon learns the truth: the marks are part of an ancient pact feeding a hidden beast beneath the town. As temptation spreads and her own brother is drawn into the ritual, Rowan must expose the horrifying cost behind the "blessing." The Mark of the Beast is a chilling Young Adult horror novel about sacrifice, inherited sins, and the courage to choose humanity over power.