The Smuggler’s Escape by Barbara Monajem

After escaping the guillotine in her native France, aristocrat Noelle de Vallon takes refuge with her aunt in Sussex. Feisty, resourceful, and determined to make her own way, she takes over the local smuggling operations, doubling their profits. But when their plans are betrayed, a man from her past steps out of the shadows to save her. Too bad he’s the last man on earth she ever wanted to see again.
Years ago, Richard, Lord Boltwood’s, plan to marry Noelle was foiled when his ruthless father shipped him to the Continent to work in espionage. But with the old man at death’s door, Richard returns to England with one final mission: to catch a spy. And Noelle is the prime suspect.
Noelle is determined to finish the smuggling run and escape back to France. She needs Richard’s help to do it, but how can she ever trust the man who abandoned her? And how can Richard catch the real culprit while protecting the woman who stole his heart and won’t forgive him for breaking hers?