Autumn, 1797. With Napoleon's forces sweeping through Europe, a young Englishwoman travels to Paris, risking her life on a secret assignment that may buy Britain vital time. Mary Finch is no stranger to adventure, but even she hesitates before accepting this new task. She must rely wholly upon a stranger, while deceiving her 'dearest friend', Captain Robert Holland. Once In France, Mary's safety rests on a knife-edge, and her colleague has secrets of his own.