In her latest in the Ravenals series, Kleypas has loosely based the heroine on a real historical figure, Elizabeth Garrett Anderson, the first (and only, for many years) female doctor in England. Kleypas' Dr. Garrett Gibson is also the lone female physician of her time and she does work in London and those are broadly the only things they have in common.
Though Garrett's skills are in evidence throughout the novel, this is a romance, so it's not really about that. On her way home one night after a long shift at a clinic Garrett is attacked by a group of men. Garrett has some defensive skills, as any woman would who has to travel alone in Victorian London, but she's not a match for multiple men. Luckily Ethan Ransom, a former detective for Scotland Yard, is nearby and steps in to assist her. The two spar with foes physically and with each other verbally and Garrett finds herself fascinated. Ethan tries to resist his attraction to Garrett because the job he does is too dangerous for him to bring her into his world, but he finds himself drawn to her in ways too hard to ignore. So Ethan offers to give her better self-defense tips, Garrett accepts, and they take the first steps on a complicated relationship.
Kleypas excels at writing intelligent, likeable protagonists. And she shows that ability here once again. Garrett and Ethan match each other in wit and strength and make for a lovely romance pairing. Good stuff.