Seventeen-year-old Katelyn Michaels plans on hating every moment of her visit to Mont Saint Michel with her father's new French wife. Once there, she is confused when she experiences sensations of deja vu and hears voices as she and her younger brother explore the medieval village and abbey. She is confronted by two unusual young men, one who insists she is there to save the mount, and the other who will stop at nothing, even murder, to stop her from fulfilling her destiny. When the oddly-dressed but alluring Nicolas slips Katelyn a strange medallion, she is whisked back through time with him to the 15th century where her Watchmen hosts tell her she is the only hope to save Mont Saint Michel from the invading English armies. Even worse, she learns those armies are led by a fallen angel intent on learning the mount's closely-guarded secret. Katelyn is torn by feelings of anger at being taken back in time, inadequacy at finding a modern solution for a medieval problem, and responsibility for the mount's starving inhabitants. She is also perturbed by her surprising attraction to the ill-tempered Nicolas. Will she stay to learn why she was chosen by the Archangel Michael and find a way to save his mount?"