I've enjoyed the adventures of the Sutherland sisters as they secretly help out a young Queen Victoria--Laurel and Ivy not only had tense, urgent missions, but the way they worked with their respective husbands was a treat to read. Colin and Holly however, were less endearing to me.
Colin's attitude and behavior was the main reason why actually. In previous novels there felt an equality and partnership in the pairings. Holly and Colin never quite reached that level to me. Colin spent much of the book 'protecting' Holly's sensibilities for a variety of reasons (he was never at a loss for those). Holly's accusation that he underestimated her resolve and strength of character are the most genuine words spoken. He was so certain that Holly would break under the faintest of hardships that he didn't take the time to get to know her. Never mind that Holly has endured quite a few hardships in her life, or that her sister's (regardless of the 'secret' reason why) lives weren't peaches and cream either. He was bound and determined to keep Holly far, far away from the presumptive horrors to the point where it got to be really irritating. It stopped being 'charming' and 'protective' around the fifth or sixth time he silently consoled himself that he was doing the right thing by not pursuing a long lasting entanglement with her.
Holly was, unlike her twin Ivy or her oldest sister Laurel, headstrong and reckless (hence the title, more apt words never spoken). She doesn't much care what the mission for Victoria is (in fact if it had been to chase down a murderous, wanted criminal she would have been off like a light quicker than you could blink!), only that it means adventure. The fact that it could also lead to a prestigious marriage as well seemed more of an afterthought honestly, and remarked on more often by other characters then Holly herself. She's clever and quick-witted, with a soft heart and an unshakeable belief and loyalty to Victoria that almost borders on the zealous (all the Sutherlands do honestly).
The ongoing sub-arc about the Sutherlands true origins gets a real step up here, becoming much more twined with the main plot then in the previous volumes. We learn a bit more about their parents and their french connections, as well as a surprising amount about a secondary villain from the first book Henri de Vere. It's a bit outrageous and I'm not entirely certain the novels needed that added layer. The fact these girls were Queen Victoria's Secret Servants was plenty enough--the added French Revolution and their parents mysterious deaths muddied the waters. This plot seemed to take precedence in the novel in the latter half, and will likely be a driving force in the fourth book (about the youngest Sutherland Willow).
Holly has always been the reckless Sutherland sister, the one most likely to hitch up her skirts and gallop astride a powerful stallion. Holly's affinity for horses leads Queen Victoria to enlist her help when a prized Thoroughbred colt disappears. To catch the horse thief, Holly must put on her best manners and mingle with the dashing Colin Ashworth, Earl of Drayton. Uncertain she can trust him, she is also powerfully attracted to him.
As Holly's growing suspicions threaten to expose the truth about the stolen horse, Colin's head tells him to distance himself. But with his heart, body, and soul all recklessly clamoring for Holly, he finds her impossible to resist...