In "Knave of Diamonds," Mary grapples with her uncle Jack's sudden reappearance and the mystery of his past, as he seeks her help in tracking down the Irish Crown Jewels. The narrative unfolds through the perspectives of Mary, Sherlock, and Uncle Jack, providing insight into Jack's motives and the historical robbery. While the family dynamics and treasure hunt aspect are intriguing, the tension of the mystery feels lacking, rendering the story more of a cozy than a gripping historical thriller. Although it may not meet all expectations, it offers a pleasant experience for fans of cozy historical mysteries centered on a husband-and-wife detective duo with familial ties.

I usually love Mary Russell and her adventures with Sherlock, but The Knave of Diamonds just did not draw me in like the other numerous great books in this series. The first third to half of the book was so slow, with a lot of history and backstory that didn't feel necessary to the overall arc. Mary and Sherlock were frequently or mostly apart, and you lost that snappy back and forth that is so much fun to read. Ultimately, I think Knave of Diamonds could have been trimmed down to almost a novella and still been just as good. Of course the plot is always solid, but just felt like a little too much filler on this one. Thanks to the author, publisher, and NetGalley for the opportunity to read and review.

This is the first time I've ever been disappointed by a Mary Russell story. I've always liked the series for the relationship between Russell and Holmes and for their investigations of intriguing mysteries; sadly, neither of those things shine in <i>Knave of Diamonds:</i> Russell and Holmes rarely interact with each other and their "investigation" is just them following after yet another long-lost relative and being given the answers by other characters.

The bright spot of the book is Uncle Jake: he's an entertaining scapegrace, and I enjoyed his (too few) conversations with Holmes.

Despite my disappointment, I do think <i>Knave of Diamonds</i> is worth reading, but I know Laurie R. King is capable of writing a much better book.

Received via NetGalley.

Utterly charmed by Russell’s Uncle Jack. Thrilled to have Mary Russell & Holmes return in a new intriguing adventure.

Another enjoyable addition to the Mary Russell/Sherlock series. I enjoyed learning more about Mary's family, as well as it was fun to "travel" to Ireland with them. This book was more straightforward than some of the previous ones. I have noticed that as time has gone on they are less complex, but still enjoyable to read. Thank you to NetGalley and the publisher for an ARC.

This is the nineteenth installment of the wonderful Mary Russell series and it does not disappoint. In this one Mary's long lost Uncle Jack reappears with his usual baggage, this time involving the theft of the Irish Crown Jewels. What follows is an interesting romp that introduces new series members in addition to the story.

This didn’t end up being my favorite of Laurie R. Kings books but it was still a solid read for me. I also made my father read it who loves her works, and he enjoyed. Definitely check it out if you’ve enjoyed her works before!

I am so happy that there is a novel with Mary’s family! I feel like the series has followed their marriage but mostly about Sherlock and the many curiosities of his family or almost family. I also really like that Sherlock allows Mary to be independent, but he still checks up on her.

I love when novels bring in real cases that have never been solved. I just enjoy the possibilities of how it could have been done, the true what-ifs.

Overall, I rate this novel 5 out of 5 stars.

Thanks to the publisher and Netgalley for this eARC.

Laurie R. King’s Knave of Diamonds is not merely a continuation of the Mary Russell and Sherlock Holmes saga—it’s a cunning reshuffle of the deck, where familiar faces play unfamiliar roles, and every card turned reveals a deeper layer of deception, loyalty, and legacy.

Set in the interwar years, the novel opens with a cryptic message delivered to Russell: a playing card—the knave of diamonds—marked with a symbol only Holmes would recognize. What follows is a transcontinental chase that threads through Monte Carlo’s glittering facades, the dusty archives of Oxford, and the shadowed corridors of a forgotten estate in Cornwall. King’s prose is as precise as Holmes’s deductions and as introspective as Russell’s internal reckonings. The suspense is not just in the plot—it’s in the emotional stakes, the philosophical undercurrents, and the quiet moments where trust is tested.

Thematic Depth

- Identity and Disguise: King plays with the idea of masks—literal and metaphorical. Holmes, ever the master of disguise, finds himself questioning the roles he’s played throughout his life. Russell, meanwhile, confronts the uncomfortable truth that her intellect may not shield her from emotional vulnerability.

- Chance vs. Calculation: The motif of cards is more than aesthetic. It becomes a metaphor for fate, strategy, and the tension between randomness and reason—a theme that resonates deeply in a post-war world trying to make sense of chaos.

- Legacy and Inheritance: The mystery hinges on a decades-old betrayal, and King deftly explores how the past echoes into the present—not just through clues, but through character psychology and moral dilemmas.

Mary Russell remains one of the most compelling protagonists in historical mystery fiction. Her sharp wit, philosophical musings, and emotional restraint make her a foil and equal to Holmes. In Knave of Diamonds, she’s forced to confront not only external threats but internal doubts—about her marriage, her autonomy, and her place in Holmes’s world.

Holmes, aging but undiminished, is rendered with a subtle melancholy. King doesn’t romanticize his brilliance; she interrogates it. His moments of vulnerability—especially in scenes where he’s forced to rely on Russell’s intuition over his own logic—are some of the novel’s most poignant.

King’s dual perspective structure allows for elegant tension-building. The alternating viewpoints between Russell and Holmes are not just stylistic—they’re strategic. Each chapter feels like a move in a chess game, with the reader piecing together the mystery from two minds that rarely see the board the same way.

Her prose is lush without being indulgent. Descriptions of place—especially the Monte Carlo scenes—are cinematic, yet grounded in historical texture. Dialogue crackles with intelligence, and the pacing is masterfully controlled: slow burns that erupt into bursts of revelation.

Knave of Diamonds is a literary sleight of hand—deceptively elegant, emotionally layered, and intellectually satisfying. It’s a novel that rewards close reading and re-reading, not just for the mystery, but for the philosophical questions it poses about truth, partnership, and the cost of brilliance.

In Knave of Diamonds, Mary Russell’s past comes rushing back when her charming yet roguish cousin Jake reappears, pulling her into a dangerous game involving the theft of the Crown Jewels. With Holmes on the case and secrets at every turn, the mix of mystery, family tension, and witty exchanges makes for a lighter, more playful adventure in the Russell & Holmes series.

The dynamic between Russell, Jake, and Holmes is a highlight, and the fact that the plot draws on the real 1907 Irish Crown Jewels theft makes it even more intriguing. A fun, clever read for mystery lovers.

Thoroughly enjoyed this latest in King's Mary Russell/Sherlock Holmes series. I've been a fan from the beginning enjoying Mary's growth as a fitting partner for Holmes (in fact sometimes surpassing him!), Their odd but heartfelt romance coupled with their interplay continues to delight and it was interesting to learn yet more of her backstory with the reappearance of her uncle who was long-surmised to be dead. I would highly recommend this addition to the Russell/Holmes canon. A thoroughly enjoyable read.

Another delightful installment of my favorite female sleuth. Mary can't seem to go anywhere without trouble finding her. Mary and Holmes return to their quiet life after their last adventure. Holmes needs to take care of some business which leaves Mary to herself. Blissfully winding down and enjoying some peace, there is an intrusion. This comes in the form of her long - lost Uncle. Mary knows his back-history and that he has a dubious past. He annoys Mary to the point that she will help him find some very famous stolen jewels. Of course Holmes pops in at an inconvenient time for Mary's uncle. Mary's brilliance and ability to adapt to the most unusual situations, has the trio trying to find this secret cache of jewelry. The Uncle has plans for the find but so does Mary and Holmes. A delightful romp and I cannot stress enough how you should pick up this book!

A wonderful continuation of this character's legacy. Plot twists and topical and timely historical allusions.

When Mary Russell’s long-lost Uncle Jake reappears at her door, he brings with him a scandalous mystery tied to the infamous disappearance of the Irish Crown Jewels—an unsolved theft that once baffled even Sherlock Holmes and may have involved Mycroft. Jake wants Mary’s help, but aiding him would put her at odds with both her husband and his powerful brother. Once again torn between loyalty and duty, Mary must navigate lies, secrets, and family ties in this tangled case.

It was fun to be back with Mary Russell and Holmes once again. This one picks up right where the previous book left off, and while it references the previous adventure, I don’t think this is one a new reader could start with. We delve a little more into Russell’s past and her family with this one.

I especially enjoyed how this fictional story weaves in with an actual event from history. It definitely made me more interested to learn about the theft. I liked the clues that came to light and how they all came together.

Overall, this was a fun addition to the series. Readers who are fond of Russell and Holmes’ adventures are sure to enjoy this one.

*4.5 stars*

A rollicking tale taking on a real-life mystery…

I have been hooked on this series since I read The Beekeeper’s Apprentice many books ago. Sherlock and Mary’s bond was stronger than ever and their unspoken understanding and devotion to each other shone quietly in this real-life mystery…

Mary’s uncle had not part of her life in years and his sudden return brought with him a case to solve. Who actually stole the Irish Crown Jewels and where were they now? And in Mary’s mind – how was her Uncle Jake involved? Sherlock had investigated the theft when it first happened and his findings were discounted. Now, in 1920’s England and Ireland, he reluctantly joined his wife and her uncle in finding the truth. Top of his mind was finding out why Jake had turned up now and what was his real motive in the search for the jewels. Mary wasn’t sure what to really think but threw herself into the investigation wholeheartedly. She was not unaware of the stories and the not so stellar reputation of her uncle but chose to give him the benefit of the doubt. The story unfolded quickly with each uncovered clue sending closer to the truth.

There was a lot to enjoy about this mysterious ‘who done it’ including a return to characters which I love. Jake, just one of the compelling, new characters added to the mix, provided another element of intrigue and complexity to the story. The relationship, the closeness, between Sherlock and Mary was still a highlight as their unspoken bond was a constant in the winding turns this story took.

The conclusion was satisfying with all the details coming together in a logical fashion with a bit of a twist at the end. I feel a need for a full series re-read now as I wait for (hopefully) yet more stories from a favourite mystery-loving couple…

Thanks to NetGalley and Random House Publishing - Ballentine for a digital advance reader copy. All comments and opinions are my own unless otherwise noted.

This is #19 in the series, and I’m one of those fans who has read them all (in order). The series follows the mystery-solving exploits of Mary Russell and her husband, Sherlock Holmes, and are cleverly written with wit, suspense, and humor.

The novel alternates between chapters told from Mary’s point of view, Holmes’ and Mary’s long lost Uncle Jake, whose sudden reappearance and request for help from Mary sets the story in motion as they travel to Ireland to find the infamous missing Irish Crown Jewels.

The book starts out a little slowly, but don’t give up as it soon improves and doesn’t let you go until the last page. Satisfying and entertaining – this was a real page-turner!

It has been over 30 years (!!) since the first installment of the Mary Russell series came out, and I'll be honest - I'm impressed that they are still going! The Knave of Diamonds sees the return of one of Mary's long-lost family members, indeed, the only blood family member that she has left. A con man with a moral compass that Sherlock is eternally trying to figure out, Jake pulls Mary into a second-chance mystery from his younger days. I'm always happy to spend time with Mary and Sherlock, and Jake is a fun new addition to the series. However, overall, this book felt a bit too light on intrigue and too heavy on character development for a character that I'm not convinced we'll see again.

Thoroughly enjoyed the addition of uncle Jake Russell as a narrator. It was really neat seeing both Russell and Holmes from the perspective of another character, and we got a lot more back story on Mary's family.
The historical mystery was based on talk life events and made for an engaging plot.
A a long- time fan of this series, I can say Ms. King does an excellent job of keeping things fresh and interesting.

Having not read any of the previous books in this series I have to admit I was lost for a bit. It isn't designed for newcomers, because the story arc has travelled so far from the canon of the Holmes work. Here, Holmes had a relationship with Alder, had a son by him. His mother is alive. Something happened to Mrs Hudson - is she alive? Is she ill? He's married to a woman (our main character) who is a fraction of his age. I have to admit, the age gap made me very uncomfortable, but there was no actual moments between them.

I couldn't decide if they actually romantically cared for each other or if the marriage had been more of a platonic meeting of the minds, a way to give Russel stability and security. I would prefer the latter but the fact I couldn't tell throughout the whole book is not great - it's obvious he respects her and her abilities but that doesn't explain exactly what they are to each other.

I'm sure if I'd read the previous ones, I would have that, but at the same time the book needs to also work in its own right.

The mystery itself, based on real events, was entertaining enough, although apart from a couple of moments of Holmes being brilliant, it was just the characters moving from one location to another, sometimes opening a safe. The side characters were the star of the show, from Mrs Walsh to Lady Vicars, to The O'Mahony. They are delightful oddballs, the jewels of the book and where the writer shines.

Russell and Holmes are finally back from the continent and ready to relax, after tending to the bees, of course. But then Holmes is summoned by Mycroft in relation to an old case - a case where Holmes was prevented by the British government itself from bringing his investigation to an official close. And while he is away, Russell receives a visit from her uncle. Readers have been given details about a few of Russell's family members (beginning with the odious aunt and cousin who were making her life miserable when she first met Holmes), but this is a relative that has remained in the past until now. When it turns out that Uncle Jake was somehow (is still somehow?) involved in that unsolved case, we are not too surprised.

As the three of them set out to find the missing Irish Crown Jewels, the interplay between them all is fascinating. Episodes that Russell has shared with Holmes are fleshed out with more detail and we start to see where Russell learned a few of the skills she already had before becoming the apprentice of Sherlock. Breaking and entering, safe-cracking, train rides, boat trips, and visits to tea shops are just a few of the activities that take place as we watch Russell become reacquainted with Jake and learn along with her about a few of the shady exploits he has been involved in over the years. The friction between husband and uncle is understandable considering which side of the law they each represent.

It is an intriguing and suspenseful adventure - made more so by our desire as readers for Uncle Jake not to break Russell's heart and for Holmes and Jake to peacefully coexist.