Katrina "Kit" Lawson goes on a camping trip only to awaken in twelfth century England. She's lost her horse, her time, and from the sword at her throat, most likely her freedom. Her captor however, allows her to remain unconfined and she fights her attraction for the baron as she searches for a way home.

Marcus Quinn, Baron of Blackthorne, is one of the king's legendary knights, known as The Devil. Until he meets this woman who goes by the name Kit, he believed himself ready for anything. Unlike any woman he's ever met, she continually challenges him, pushes him, and enthralls him. Day by day she ingrains herself further into his life, changing it for the better. Unfortunately, the king has plans for him, plans that don't include Kit. He knows he has to let her go but he rebels against the very idea.

When she vanishes, he vows he will find her once more. Will these two lovers find a way to be together for all time? Can Kit trust that once made it will never be broken? Perhaps. It is after all, A KNIGHT'S VOW.