Wonderful book. The story is about a girl who is a foundling and taken in (with her twin brother) by the vicar of the church where the babies were deposited. The vicar marries soon after taking in the 2 babies, but then he dies and his widow remarries, so the two foundlings grow up in a wealthy family as the very poorest of non-relations and have this fact rubbed into their faces at every opportunity. The brother goes off to fight in Portugal and is killed there, and the girl, the heroine, becomes engaged to a self-righteous and pompous vicar because this seems to be her only option to improve her situation. On her way to her fiance's home the heroine's carriage breaks down and the carriage driver goes off to look for help, leaving the heroine and her maid by the roadside. Robbery and an attempted gang rape ensue, with the hero, who is traveling on the same road, luckily saving the women from a dreadful fate, but is himself shot in the arm as a result.
For most of the rest of the story the heroine, named Onyx, is nursing either the hero as he recovers from his wound, or the hero's brother, who is dying of cancer. Lots of gory medical details and historical medical details which I trust, knowing Carla Kelly's writing, are true, such as the one where a patient's own feces are applied to his bedsores "to draw out the black humors from his body". Hmmm ... The attempted gang-rape scene is pretty graphic too, so this book is maybe not for the faint-hearted or innocent, even though technically it qualifies as a "clean romance".
All ends well, when Onyx finally decides that marriage to the pompous vicar would be insupportable, but at that point a very curious secret is revealed to her which makes the heroine's treatment by one of the secondary characters in the story (who are all fully-fleshed and real people) quite strange and inexplicable, at least from my POV as a parent. This raised a few unanswered questions about the story, which up to this point had seemed quite straighforward. But this is a minor quibble for an otherwise very well-written, well-researched and emotionally intense book.