The story is set in England on the eve of the Wars of the Roses. Tensions between the Houses of Lancaster and York simmer beneath the moors, religious authority and secular rule vie for power, and plague and pillaging cast a shadow over the common people. Mu Lin, a 21st-century doctoral student in materials science, transmigrates by accident after a particle collider accident and falls into this wild land of swords and faith, becoming an "outsider" of unknown identity. From the start, he faces the deadly accusation of being "possessed by a demon."
