Rival's Break by Carla Neggers

I'm pretty sure I've never read a book that opens with a rash of seasickness, but this one does. Well, really it opens with Colin's brother, Andy, getting married to Julianne (Declan's Cross) but Colin and his marine patrol brother, Kevin, end up leaving the reception to investigate the illness. Colin is surprised to recognize one of the victims as an undercover agent.
From there, they get caught up in the world of nerve agents and mushrooms while Aoife Byrne's work becomes part of the story once again. Were the people on the boat targeted for some reason? Or is someone after the chef whose scientist father is even now in the throes of death?
The mystery was... very confusing. The story was fine but I had really no idea what this did to move anything in the Sharpe & Donovan universe forward.

Two and a half stars
This book comes out August 27th
Follows Impostor's Lure
ARC kindly provided by Harlequin-MIRA and NetGalley
Opinions are my own

Impostor's Lure by Carla Neggers

Tamara McDermott is supposed to meet her daughter for her 21st birthday. When Tamara doesn't show, her daughter isn't worried (as a federal prosecutor, she is often absent from family dinners), but Yank, Colin, and Emma are. Trying to find her leads to an increasingly odd puzzle as someone connected to her is found near death and another man has disappeared. Personal bonds are tested beyond all belief in this addition to Sharpe and Donovan.

A sad book (which marks it down for me at this point in my life) but most readers of the series will enjoy it.

Three stars
This book came out August 21
Followed by Rival's Break
ARC kindly provided by NetGalley

Thief's Mark by Carla Neggers

We've learned a lot about Oliver York in the previous 6 books in this series. In this book, he comes into even more focus when one of the man who kidnapped him as a boy, returns. And then dies in Oliver's arms. Oliver is the easy person to pick as prime suspect. But there is, of course, more to the story.
Emma Sharpe and Colin Donovan are on the last day of their honeymoon when the call comes in that Oliver is once again embroiled in a mystery. Also on the scene, Oliver's gardener, Henrietta, (a former British secret service agent) and a man who has been with him since childhood, Martin.
 Weaving together the characters that Ms. Neggers has created in the Sharpe and Donovan universe, the dead man visited Father Finian the day before he died. I like that there is a concrete reason for previous characters to be woven in, they're not just plugged in willy-nilly to remind you that this is a series.
Books can always be read out of order in a series but I definitely wouldn't recommend it for this one. I think regular Neggers readers are going to be pleased with this addition to the series.

Three and a half stars
This book comes out August 29
Follows Liar's Key

Liar's Key by Carla Neggers

Colin and Emma are off on another adventure, one that is happening right before their wedding. A friend of Oliver (the infamous art thief from previous books) and Emma's grandfather (famous antiques dealer) is killed. Right after he brings up the suspicious theft of some mosaics. Also involved, a legend of the FBI, one who slipped up only once in his career, but it was with a confidential informant. A CI who is also in Heron's Cover. One who might have some information about what happened with the mosaics.
The mystery was easy enough to solve but it was rather shallow. Not a lot of information. There were so many people that were revisited and introduced (including Father Bracken's sister, Mary). Not my favorite Carla Neggers but not horrible either. Regular Sharpe & Donovan readers will enjoy.

Three stars
This book comes out August 30
Follows Keeper's Reach
Followed by Thief's Mark

Keeper's Reach by Carla Neggers

A solid addition to the Sharpe & Donovan series.
This time the stories of Emma and Colin coincide with those of Colin's brother and his old flame, Naomi. Naomi is in England working. But she took a quick side trip to the Cotswolds where she interacts with Oliver's (big-time thief Colin and Emma were chasing in the first four books) handy man who has been hit on the head. But was it an accident or did someone knock him out? And for what reason?
Nothing spectacular but it is a solid addition to the series that longtime readers will enjoy. I would suggest that new readers start at the beginning. It's nice to see Emma and Colin progress but it does occur at the expense of Naomi and Mike's story.

Followed by Liar's Key

Harbor Island by Carla Neggers

Image linked from Goodreads

I would most definitely read this series in order. There's a mystery that's been building since book one and, while you can maybe drop in, I wouldn't recommend it.
The story starts off with Emma Sharpe getting a phone call from filmmaker Rachel Bristol, saying that she (Rachel) has information that can help solve a decades-old art theft. But when Emma gets to the meet site, Rachel has been killed. We then spin into one of Neggers books, neither better nor worse than the previous books in the series. If you've read the first three in this series, you're well-prepared for this book.
We get new insight into old characters as well as meeting new people. The cast of characters is getting a bit unwieldy but it's not as bad as some other series. At least the people all fit in with out being shoehorned.

Declan's Cross by Carl Neggers

STOP! Do NOT read this book if you haven't read the other two in this series. You will not understand most of what is happening. You might still get some enjoyment but really, not as much has having the more extensive background of earlier books in the series.
Julianne is one such character we met in Saint's Gate and Heron's Cove. She dated Colin's brother Andy for awhile before he inevitably broke her heart. When offered a chance to study marine life in Ireland, Julianne jumps at the offer, even though she just met Lindsey. One problem, Lindsey isn't there to pick her up. Well, Julianne is a big girl who can get herself up to the cottage where she's staying. But Lindsey never shows up. At least, not alive.
Luckily, Emma and Colin are in Ireland and on their way down. Not to check up on Julianne, at least not ostensibly, but it is quite the coincidence that she ended up in the same small village where a spectacular art theft (a running theme in the books) took place decades earlier. 
Like the other Sharpe and Donovan (and really, any of Neggers' books) series, this book is a tangled series of intersecting stories. I sometimes have to put these books down and just think for a little bit and read something less complicated. But don't put it down for too long or you'll have to start back at the beginning.
I probably would really rate this at a two and a half but bonus points for the grand descriptions of Ireland. There are too many rehashings in this books, not just from the other two books but from this story as well (Andy's love her/don't love her, Father Finn's past) and also some story leaps (Lindsey's father might be connected to the art theft?) that just strech a little too much.
Will I stop reading this series? Probably not. I loved the first book too much and hope that I can find that level of enjoyment again.