I received this book through "NetGalley".

This is the 1st book that I have read from this author and look forward to reading many more. The story begins with Manhattan suffering a blackout from an unnamed source. As a result, Jessica was called from her FBI Training assignment and put on a task force. Her assignment was to locate Theo Cray. Many of the task force team thought he might be involved. Jessica tracked him down to Myanmar where he was being held. She was able to get him free. Jessica questioned Theo because she wasn't convinced that Theo was not involved. As she worked with him more, she finally began to believe him.

Jessica and Theo began the search and starting looking into an individual known as "The Warlock". Eventually they were able to locate him, but then Theo was arrested and Jessica was transported to a site where she was held.

To discover whether Jessica and Theo regained freedom, what individual was responsible for Theo's arrest and what reasoning "The Warlock" had causing the blackouts, then you must read this book. Once you start, it will be hard to be put down.

Thank you Thomas & Mercer and Netgalley for allowing me to read this arc. I don't know why this series was never on my radar before this, but now I have to read them all. The book starts out with a bang! Then the scene moves to jungles of Myanmar, and I was puzzled about what was going on. I kept reading and it all started to make sense. What a cat and mouse game! The story was scary in a 'could this happen' kind of way. The characters were great, and I'm so excited that Theo has his own series as well as the books with Jessica.

I went into this book expecting science fiction but soon realized that this book was more of a thriller. However, the plot and the characters were so well developed that I found myself quickly immersed in the story and enjoying the ride. Well done!

This book is so addictive that it’s not a good idea to pick it up if you have other things to do, like working or sleeping. I’ve read all of the Theo Cray series to date, and I love it. I’d never read the Jessica Blackwood but now I will. Together, they’re unbeatable. Theo’s knowledge of patterns and Jessica’s resourcefulness are so much fun to read about. The plot is fast-paced and full of twists. The chemistry between Theo and Jessica is intense and their dialogues are full of humor. The rhythm doesn’t let up, it was getting more and more intense and there was less and less to read and then…the ending blew me away. I hope this is the beginning of a beautiful friendship because I want more. This is fiction at its best.
I chose to read this book and all opinions in this review are my own and completely unbiased. Thank you, NetGalley/Thomas & Mercer!

I was happy to snag an advance copy of Andrew Mayne’s “Mastermind” with thanks to Mr. Mayne and Thomas & Mercer.

I’ve read most of Mr. Mayne’s novels and this one delivers on his trademark crazy stunts and practical science. He has brought together Theo Cray and Jessica Blackwood, stars of two other series, to catch the nasty serial killer known as the Warlock and save the world.

It’s action, action and more action, with little room to breathe while our hero and heroine appear to build strong mutual feelings. They don’t sleep much either, as they jump from crisis to crisis around the world (with what must be highly efficient government transport included). I can mention that their adventures include hungry escaped monkeys, zombie sightings and disappearing cities. . . without any risk of spoilers.

For the rollicking good fun and their clever problem-solving, I bestow 5 stars. But the resolution was overly rushed and left too many loose ends for my taste, so I have to round down to 4 stars. But I will devour anything that Mr. Mayne sees fit to publish, with gusto!

Sorry to say that I only made it half-way through Mastermind. It starts out with a bang, and then just takes a mad dash down hill. I thought the attack on New York's Manhattan Borough would be central to the story, but soon we were in jungles in Myanmar. Later we went to a chimpanzee camp, where we were told things about the chimps that were not all that exciting. I felt that instead of reading a mystery or a thriller, that I was in science class. It was not entertaining. Perhaps the author redeemed the novel later, but I couldn't stick around. I'd rather play hooky from school.
Thanks NetGalley for the ARC.

I always know I'll be in for a mind-bending thrill ride when I pick up an Andrew Mayne novel, and MASTERMIND did not disappoint.

Mayne's Jessica Blackwood thrillers are some of my favorite novels of all time, and I've enjoyed his Theo Cray novels as well. Together for the first time here, Jessica and Theo's brilliant minds complement each other. It was a bit jarring at first to have each of them with first-person narratives, but once I got swept up in the story, it worked. I hope there will be more to come of their adventures.

Mayne's background as a magician comes through in his approach to presenting baffling mysteries that have satisfying resolutions.

Thanks to NetGalley and Thomas & Mercer for the advance reader copy in exchange for my honest review.

4.5 stars.
This book was exactly the type of book that I needed to read. It is not one of those books that you can half pay attention to, you really need to devote your brain to it. The plot sucked me in right away. Manhattan goes dark. All cell phones and electronics do not work anymore. But why? And what is going on while everyone else is blinded by the darkness? That is what FBI agent Jessica Blackwood and scientist Dr. Theo Cray are out to uncover. (And just like any other review I write, I don't like the give away anything in the book as I am a fan of going into the book with an open mind so that I can make my own assumptions only to be stunned when I am done with it). It almost reminds me of one of my favorite shows, '24' (it does not take place over the course of a day like the show does). Clear your head and pay close attention to the details. Mastermind does not disappoint. Thank you to NetGalley and the publisher for the advanced copy in exchange for my honest review.

Great read! Really enjoyed the merging of the Jessica Blackwood and Theo Cray series. Mayne did a great job of staying to true to the main characters personalities while transporting them into the future (from where their respective series had left off). I would have liked to know what happened to Damien but I really enjoyed the inclusion of other characters from the series. I hope this isn't the end of the road for either character.

I seem to recall reading something that had Theo Cray in it, bu clearly, I'm thinking of someone else, as the series featuring Cray is not something I've read. Likewise, I have not read any books in the Jessica Blackwood series.

That said, this books, labeled as Blackwood/Cray #1 seems to be a new series where thy will be together to investigate oddball things that may happen - like a mysterious blackout in NYC that appears to be swirling with electric energy and which also cut out power to almost everyone in the bubble and caused electronic devices to stop working.

We get a scene of Cray being liberated from a jail in a foreign land, and it appears Jessica Blackwood possesses skills ranging from hand o hand combat to forging paperwork. It's the latter that allows her to get Cray out of the hellhole he's in.

Of course, there's a catch to all this: the FBI, for whom Blackwood works, needs him and Blackwood to look into the phenomenon they've taken to calling The Void. Blackwood believes it's the work of that typical fictional villain, Michael Heywood, AKA Warlock who seems to have the world at his fingertips and who managed to escape prison during a transfer.

What follows is a romp around the globe, with clues coming from the oddest places: a zoo where chimpanzees have been stolen. A "research facility" in the Chernobyl zone, where the men are practically zombies, but ordinarily healthy otherwise, no matter what ailment(s) they may have had before..

Together, the no nonsense, hyperfocused Blackwood, and the talks before he thinks Theo Cray race around the globe, looking into odd incidents, thefts from datacenters, and two more Voids in Seoul and Singapore. In their way: people paid off by Heywood, and eventually a face to face with Heywood, who demands Cray also be there, despite Cray not having any direct connection to Heywood, so Heywood can detail the ways the he is better than Cray..

As far as stories go, it isn't too bad. There's enough suspense that then turns into a "the clock is ticking" story when the threat of yet another Void is hanging over their heads to keep things moving along. I did like the banter between Blackwood and Cray, and there is the typical internecine fighting between federal agencies, both of which ring true. The ending is a turn the tables type, and that works here in the universe of this book. The writing is good, although some of the backstory drop-ins felt a little forced. That does not really break the narrative, however, and while some of them were rather long - necessary for some of the technical stuff that most people don't know or with which they are not familiar - but I am not dinging it for this.

A solid four stars.

Thanks to Thomas & Mercer and NetGalley for the review copy.

The challenge in this book is the initial pacing.

The book starts with a bang. There’s so much going on and it’s really exciting. You’re anxious to find out just what’s happening in the world and why. But then, the book slows down to a rather glacial pace.

I admit. I almost stopped reading.

However, I kept going and I’m glad I did. If you can get over that little hump, you get a truly exciting read and a plot of epic proportions – like possible end of the world as we know it proportions. The actual reason behind everything is fascinating and unexpected. I loved what the author gave us here.

I ended up thinking this was a four star read. Try to get past that slow patch – the surprises the author has in store for you are well worth it!

*ARC provided via Net Galley

I love the novels of Andrew Mayne and this also brings together two of my favorite characters, Jessica Blackwood and Theo Cray, against the Warlock which makes it even more special.
A strange storm and the escape of the Warlock set in motion the events of this novel.
Without a doubt a must-have novel for those who love action and twists that keep you trapped from start to finish.

⭐⭐⭐.4 stars
This is first in the Theo Cray and Jessica Blackwood thriller series.
FBI Agent Jessica Blackwood has had her own series but I hadn’t read any, I wasn’t sure if I should go back and read one.
This story starts with a mysterious situation causing complete darkness in Manhattan.
Jessica teams up with scientist Dr. Theo Cray and they suspect this was caused by a serial killer known as ‘The Warlock’.
The Warlock ~ aka Michael Heywood was introduced in a Jessica novel and now he has escaped.
He is extremely clever as are Blackwood and Cray.
‘Mastermind’ is the perfect name for this story. It is truly a ‘mind’ game. I believe I will have a fun and lively discussion about this with was 21 year old grandson.

I enjoyed reading more about Andrew Mayne the author. He is a magician who started as an illusionist when he was a teenager and worked behind the scenes for Penn & Teller, David Blaine, as well as David Copperfield. He currently hosts the “Weird Things” podcast.

Want to thank NetGalley and Thomas & Mercer. This file has been made available to me before publication in an early form for professional review purposes.
Publishing Release Date scheduled for September 14, 2021.

3.5/5 stars for me. While I found this storyline intriguing enough to hold my interest, I found the overall story to be ant-climactic. Parts of the book became a little too scientific for me and hard to follow so I skimmed some parts. I did enjoy this book and I thank NetGalley, the author, and publisher for the opportunity to review this ARC.

If you like the Jessica Blackwood and Theo Cray books this seems like an obvious book to read. It’s action packed, science packed, and two of the best protagonists of Andrew Mayne. I actually get a little scared when I read his books because the plausibility of these weird things happening is so high. I liked this book too much and I hope there will be more with these characters again.

Mastermind is a top-notch thriller, complete with a long string of sequential clues that the protagonists have to follow in order to get to the truth. I found Mayne to be a bit cumbersome in earlier books in this "dual series" but he has clearly hit his stride now. This book is engaging and compelling, a real page-turner!

My thanks, 'once again" to Thomas and Mercer, Andrew Maybe and Netgalley.
This story just didn't work for me. That's not to say that it wasn't brilliant. O.K. that's just a turned lie!
The attraction between Theo and Jess is um...good! I even felt the heat! But, they are two separate beings who could never connect for too long!
So? This was a fine and boring story. I was not engaged, and I like Jessica just fine. But, no apologies! I'm here for Theo Cray!
I'm sure that Mayne has great books out there. I'm not interested. Same reason that I don't watch any magic shows. I hate lies and falsehoods. I always search for a truth.

Wow. This book was wow. After reading Ola’s review about a book by this author I went on NetGalley to see if the ARC was still there. It wasn’t, but there was this one by the same author and so I decided to try this out. And it was an amazing decision. (And I am quite grateful that it was a read now book, too!).

I know that the book would come out in September, and so maybe it is a bit early to write this review, and I thought quite a lot about just writing it now, and then wait some more to post it, but then I decided to just go with it, and then in September I would try and share it again because this book deserves some love and some hype!
I also thought about the review itself, or at least I have tried, but I cannot promise anything here. I would try to write things in a orderly fashion, and I would try to make sense, but… but I cannot guarantee it. Be warned!
Because this book is so big. There is just so much in there, and I was creeped out by it, I was mesmerized by it and I couldn’t put it down. At all.
It is a riveting story, with some impressive characters, and a writing that flow so good that you would reach the end without noticing it.

In this book the two main characters are the main characters of two different series by this author, FBI agent Jessica Blackwood, and Doctor Theo Cray, computation biologist. This is my first book by this author, but now I have to go back and read both Blackwood and Cray’s series, because they are amazing characters. And together they are over the top. They are exceptional individuals, masterminds in their own right. Both of them have their strengths and weaknesses and they completed each other, in some ways. Both of them are strong, determined characters, with amazing minds and skills, and see them working together was a real pleasure. Also, the story is always narrated in first person, but we alternate between Jessica and Theo’s POV, and sometimes it wasn’t immediately clear who was speaking. And trying to guess who it was was a small pleasure too.
I really loved them both, and I am looking forward to see them again. I also hope that there would be more books of these two together, because I need them! (And I need them now!).

Aside from the amazing characters, we have a complex plot, that would take you in some places that are better left alone. Really, we get to see up and close how the mind of a sociopath with a god complex works, and it was scary. But it was not scary because of the evil of it, or its being alien, but it was scary because of it realness, because of its possibility. And the sad thing is that all that we get to see in this book it is true. It is not so far-fetched (okay, it is not something that can so easily happen, but it could be. ) and the reaction that it gets from the different characters, and government agencies it is, sadly, the most probable and real one. With all the moral and ethical implications. It was quite scary. Really.
But this aspect was also one of the strongest features of the book (aside from the amazing characters, I have mentioned them, right?), because we have a catching thriller, with a mystery to solve, but we have also a lot of moral and ethical implications in there. And if you just want to have a nice thrill out of it, you can do it, but if you want to take the time to follow its line of reasoning, you can also do it. And it would take you to some scary places, that for sure.

And, last but not least, this is an unputdownable book. Really. Between the characters, the plot, the really fast-pace, putting it down it is almost impossible. It is the perfect book to read in one sit because you just need to read one more page, and one more page, and wait! I need to know what would happen now. And so on, and so on. I couldn’t do it in just one sitting, because life is an harsh mistress and they tell me that I need to go to work in order to be paid (go figure!), so I needed to stop the reading a couple of time, but I loved it from the first line to the last one. And it is just so hard to put down!

This was also the first book that I have read so far in which COVID is mentioned. It is not a book centered on it, and it is not about plague and epidemic, even if they have a place in this story too, but it is a book that is set in the world after it happened. And it was… strange. In some ways.

Anyway, my only complaint about this book is that I have read it now, but it won’t come out until September, so if there would be a sequel, the waiting would be just so so so long. And this is just sad. So so sad!

Parts of the book might have made a bit more sense if I'd read previous books in the Jessica Blackwood series, but I don't think they are necessary to enjoy the book.

Near the end, I was a bit worried that the entire book was just a set up for one line that perhaps has just a bit too much to do with the current world situation, but thankfully it all came together and delivered a decent conclusion.

Good book.

The best of both worlds – strong female, conspiracy thriller. And Theo Cray, you’ve got to love that guy. I totally enjoyed this book and can’t wait to get my hands on more by this author.

Manhattan is hit with a weird electric storm, which creates black outs and all electronics no longer work.

FBI special agent Jessica Blackwood is handpicked to work on this case – called the Void. She’s partnered with Dr. Theo Cray and together they try to solve the mystery behind the Void – how it was caused, who caused it and why it was caused. Jessica thinks it’s her archnemesis, Heywood.

It’s not stop action that will keep you teetering on the edge and you won’t be able to turn the pages fast enough.

HIGHLY RECOMMEND