Octagon: A whiplash spy thriller for fans of I Am Pilgrim

by C. J. Merritt

Brought to you by Penguin.

The whiplash-inducing spy thriller, for fans of Scott Mariani and Black Doves.

A DYING RUSSIAN SCIENTIST
confesses to his children what he did as a young man.

A MURDERED SPY
shares vital intelligence before he’s ruthlessly assassinated in the English countryside.

A RITUAL KILLING
hidden in a forest clearing in Sweden hints at something much worse.

FORMER MI6 AGENT RUNNER
Stella McRae is the only person who can be trusted to investigate now her former employer has been compromised.

EX-SAS OPERATOR
Tommy Kane has always had Stella’s back, but as the threats against them escalate, will his formidable skills be enough this time?

OCTAGON
A devastating plot against the West is already in train. Only Stella and Tommy stand in its way. And time is running out...
‘A freight train of a novel. Exhilarating, raw, unmissable’ DAVID McCLOSKEY
‘Crackles with tension. Brilliant, exciting and worryingly believable’ CHARLES BEAUMONT

'Octagon bleeds authenticity from the first page to the last. Read it today!' JACK CARR, #1 NEW YORK TIMES BESTSELLING AUTHOR OF CRY HAVOC
'An espionage novel that moves fast and hits hard' M.W. CRAVEN
'A blistering thrill ride' VASEEM KHAN, author of the Q Mysteries
'A smart, slick, adrenaline-fuelled adventure for fans of Ludlum and Fleming' CHARLES CUMMING


C. J. Merritt 2026 (P) Penguin Audio 2026

Genres: Mystery, Espionage

Audible Audio

Published May 28, 2026

Reviews

[Dee Groocock · Rating 5 out of 5]

Review of advance copy received from publisher.

Stella McRae runs her own private investigation company after leaving MI6 under a cloud. Struggling to keep the company going, as well as continuing to employ Hoss, an IT whizz, things change for Stella following a phone call from one of her former colleagues, Peter.

When Peter is found dead, Stella enlists the help of Tommy Kane, who is Ex-SAS. With Tommy and Stella heading off to Sweden, Hoss stops behind to help with any leads they find. When they come across a ritual killing, Tommy and Stella are in a race against time to get away and not be framed for murder.

What a gripping read Octagon is! I loved the action throughout the story, and the plot was plausible and held my attention.

The three main characters were well thought out and worked well together, they worked off each other’s strengths.

This is a superb spy thriller that caused my heart to race more than once!

[Kim · Rating 3 out of 5]

3.5 stars
Anything catering to the fans of I Am Pilgrim is sure to entertain, right? Yes, to a point. Though Octagon was a pretty good yarn it would be a stretch to reach that high bar. It seemed more in line with a Dan Brown novel. Plenty to enjoy, though. A multi-country quest to find baddies and save the world, likeable characters and rather detailed violent action scenes (though not my thing). I wanted a fun yet tense adventure and did get one but felt it was a bit tame, possibly lacking dimension and grit. I know, that doesn't mesh with the violent action but it came across as safe and not really perilous. I didn't feel anxious or worry for Stella or Tommy one bit throughout.

Though I liked Stella and Tommy and their partnership, Tommy came across as a copy and paste ex-SAS, rather mechanical. The attempt was made to flesh him out but it didn't click for me, I'm sorry to say. Stella, on the other hand was just rife with contradictions. As a former MI6 agent I would have expect a certain level of professionalism and capability but all she brought to the table was good looks, a winning smile and an ability to charm anyone necessary. She felt more like a frightened, screaming female sidekick from an 80s adventure film.

Octagon had a promising start, feeling dark and portentous, but gradually I lost interest and by the end I was happy to move on. Full of potential, I grant you, but just lacking that extra little spark that makes it a novel I rave about and want to pass on to friends. But C.J. Merritt gets full marks and I look forward to future efforts as, clearly, a natural storyteller.

[Guy Hamilton · Rating 3 out of 5]

I was really disappointed by this book.Utterly unoriginal, a plot that was a reprise of 20 other thrillers plots I read on hoping that it would improve, alas it didn't.To equate it to I am Pilgrim is disingenuous , it has none of the originality that Pilgrim had.
Ex SIS operative, plucky girl running a small shoestring private intelligence company with young tech nerd, mentor contacts her, mumbles some weird code conversation, off to Sweden to find weird corpse art installation pursued by far right involved in some dastardly plot involving wad multiple terrorist attacks, shadowy mastermind called 'The master` etched etc.
A highly unoriginal thriller that failed to thrill.

[Carey · Rating 2 out of 5]

So disappointing - appalling cardboard characters - treating the reader as stupid - boring baddies.

[Ceecee · Rating 4 out of 5]

4-5 stars

Uranium makes its circuitous way from its original USSR stock pile to the Turkish port of Trabzon, from here it would make its way to Tehran. However, before that can happen, gunfire erupts into the warm Turkish night and the Chechen mafia smugglers are killed.…
A month later, Stella McRae ex MI6, and now the owner of a private intelligence company, receives a duress code from her former head of Station which takes her to his Norfolk home. His behaviour is odd, he’s not making much sense, he gives cryptic clues but stresses that what he’s hinting at is very serious, that it has it its origins in Sweden and that Stella must trust no one. Shortly after their encounter, he’s found dead and so Stella knows she has no choice other than to head to Sweden taking the only man she knows will protect her, Tommy Kane, ex SAS. The clues lead them to Grånmyran Forest where they discover a sight so shocking it’s the stuff of nightmares and pure evil. It’s soon becomes clear there’s a devastating plot about to be unleashed in Europe and it’s a race against the time. This is Octagon.

I love a good exciting political thriller and this is precisely that. The plot is gripping, it’s very compelling and told at a fast pace with little breathing space for Stella and Tommy as they pursue ruthless plotters across Europe. The multiple locations are used very effectively in a slick, believable, authentic, well connected complex and intelligent plot. There truly is never a dull moment and the danger levels start high and reach acute, life-threatening situations. Kudos to both Stella, Tommy and Hoss back at Stella’s office for their bravery and intuition. Although the plot is complex, it’s not hard to follow as it barrels and twists its way to an exciting and all too believable conclusion.

This is a very well written thriller, I like the way the author adapts the writing style to different situations which results in the increase of suspense and tension.

Overall, this is a very good, credible political thriller and I hope to ‘meet’ these characters again as I look forward to reading more from this author.

Great cover too - which isn’t visible on GR??!!

With thanks to NetGalley and especially to Michael Joseph for the much appreciated early copy in return for an honest review.

[Sarah · Rating 5 out of 5]

Stella McRae left MI6 under a cloud and has set up her own investigative company along with her only employee, Hoss. As with any new business, it’s struggling to get off the ground. After a call from an old colleague, Stella finds herself with a mystery to solve that could have devastating affects. She soon recruits Tommy Kane who is struggling with his own demons but has the skills she needs.

The story pretty much hits the ground running. The only thing Stella has is a cryptic clue to point her in the right direction. She is not prepared for what she uncovers, as is the reader. The one thing we can be sure of is that danger lurks around every corner and the closer that Stella and her team are to discovering the truth, the more serious it gets. We are transported to different countries across Europe which in any other circumstances would be great, sadly for Stella and Tommy they find themselves in strange countries running for their lives.

The three make a formidable team with each playing a very important part. Stella has the brains, Tommy the muscle and Hoss is a computer whiz. I was hooked with the way they work and how discovering small clues, turned into something bigger and scarier. It ends up not only being their own lives they need to worry about but for many others and it’s a race against time to whether they can solve it in time and not only save themselves but others as well.

Octagon is a fast paced, action packed read. There are plenty of thrills and chills in store for it’s reader. I literally could not put it down as there were so many twists and turns and the story just kept getting darker as well as more urgent. It would make a brilliant movie with all the action and espionage. It’s very much a story of power and corruption with Stella and Tommy being the underdogs with you rooting them on. There are so many hair raising moments and it is truly an unputdownable read. An addictive page turner that will send your pulse soaring!

[Andy Wormald · Rating 5 out of 5]

Buckle up, strap yourself in and enjoy the ride, this will be one of my top reads of the year, a razor sharp, smart, intelligent read.

It’s exhilerating, the pacing the way the story flows and moves, it left me breathless, an extraordinarily rich, descriptive read.

No plot spoilers here, you need to read for yourselves without any pre-conceived ideas. This was a story where the opening prologue perfectly set up the premise of the book, it gave me the sense that I was in for an deep and exciting read, it didn’t disappoint. There is a tangled web of intrigue at play and unravelling it comes at a price.

A book where the plotting is complex, slick and taut, though plot is nothing without character and in Stella McRae and Tommy Kane, the author has created two which standout in the memory bank, Stella is particularly interesting, extremely perceptive, deeply intelligent, someone who tries to stay on the right side of the law, a fierce thoughtful person. Tommy Kane though is a no nonesense type of guy able to quickly analyse any given situation especially when there is danger lurking, however, underneath this rugged exterior there is a person clearly troubled by past events to such a degree that his decision making isn’t always what it should. I love the way that they seemingly spark off each other, always looking out for each other. The author has created a raft of characters who you can picture in your mind.

This is a pacey read brought about by the plot which has a short time frame of events, equally danger lurks around each corner and suddenly the hunters become the hunted in a race which moves swiftly between countries.

You can feel the suspense and danger on the page, the writing heightens the tension to such a degree you feel the hairs on the back of your hand stand up, the fight scenes feel full of authenticity, through out the book the narrative leaves you on edge fearful for the characters as it races in to its dramatic conclusion.

This is a book which doesn’t let up, it’s relentless, one important note, I found the premise of the story wholly believable and in someways that is a frightening thought, but it is that belief that me totally enraptured

Some books leave you wanting more, here is one such book, it has the cinematic quality, it is a compelling and highly egaging read, cannot recommend this enough

[Olivier Santamaria · Rating 4 out of 5]

Stella McRae, an ex-MI6 agent now running her own private intelligence company, is contacted by an old friend from the Secret Service about an imminent terrorist plot to destroy the lives of innocent people across Europe. Before Stella can establish the exact nature of the plot and its protagonists, her friend gets brutally murdered.

With few clues to work with, Stella embarks on a wild race against the clock to uncover the truth and unmask those responsible. She is assisted by Tommy Kane, an ex-SAS soldier in charge of her protection, and by Hoss, a young computer genius who can access any relevant information on line. Together, they form a formidable team but the people they are chasing are not only powerful but also determined to not let anything or anyone get in their way.

I found this novel to be fast paced, tense and action packed. The story line is well constructed and keeps you on your toes from beginning to end. The threats at the core of the book are also very credible in today’s world. I thoroughly enjoyed reading Octagon and am already looking forward to the next book in the series.

Many thanks to NetGalley and Penguin Random House for the advanced copy of this book in exchange of an honest review.

[Daphne Sharpe · Rating 5 out of 5]

Stella McRae previously worked for SIS/MI6, and how now set up her own private investigation agency.
When an ex- operative friend warns her that an event has been set in motion, worldwide, which will result in thousands of deaths, and the then said agent is murdered, Stella contacts a trusted ex SAS friend, Tommy, to help her find the killer and discover what the threat is.
This quest to prevent the planned destruction in eight major world cities, leads them to an “” end of days “ cult with echoes of far right politics.
Tommy and Stella find that taking care of vulnerable and innocent bystanders is dangerous work and needs must prevail in order to protect. These do include descriptions of torture and inventive methods of killing enemies, the nervous reader may not get much sleep!!
Their methods may be questionable, but both these characters are very relatable and likeable, with a real zest for life, considering their life style choices.
This novel is graphic, gory, visceral, inventive, highly topical and utterly believable in these fast changing times of political turmoil, and a general lack of trust in politicians and the agencies of law and order.
An intriguing and disturbing thriller, a quite wonderful and engaging read. Buckle up for an exciting ride!

[Anne · Rating 4 out of 5]

Octagon is exactly my kind of read. It has everything I like - good writing, an all to believeable plot line in todays world and plenty of action, thrills and suspense. Stella McRae, an ex MI6 officer meets Peter, a former colleague who hints of a terrorist plot by an unknown organisation who are everywhere and to trust no-one. When he is found dead shortly afterwards Stella decides to look further into his claims helped by Tommy Kane, ex SAS and her assistant Hoss. Stella and Tommy travel to Sweden and find a ritual killing in a clearing and with Hoss helping from home they follow all the leads he uncovers. This is a great read, the story flows easily and I loved the different country settings and multi layered threads woven into the story that really increase the tension and suspense. The cliff hanger chapter endings just made me want to know what would come next. I really liked Stella, Tommy and Hoss. I hope the author has plans for a second book with these characters as I'd definitely want to read it. If you like spy thrillers then this is for you and I'd recommend it.

4 stars

[Daniel · Rating 3 out of 5]

Got it due to it being marketed as for “fans of I Am Pilgrim”.

It could not come close to it. Finished I am Pilgrim right before starting this book. It was not a good read for me.

The fast pace was great, and I like the approach of each chapter titled with the city in which it plays out. Other than that, the was unnecessary coarse language and blasphemy. At times, character development seemed a bit shallow. I did not like the need to mention how whole bunch of social media’s that are present today, no matter how modern you want to make the book. It seemed out of place to read these, as well as mentions to a popular first person shooter. I understand why it was there, it is just, for me, it stood out too much and made it awkward when simply a “trawling social media” would have sufficed.

The main fun action part I enjoyed, but that was only a small section towards the end of the book.

I also may have encountered ~5 or so cases where a sentence just did not make sense.


Overall, just seemed like another standard thriller trying to be placed on par with I Am Pilgrim, which could not be achieved.

[Dave C · Rating 3 out of 5]

I was really excited to get my hands on this book, being a big fan of spy thrillers, especially those involving international plots. And that cover. So good!

This started very well, with a very engaging first third as the conspiracy unfolded. The characters were likeable enough but I soon found myself finding some of the dialogue a bit forced. The plot itself is strong, with clear motivations on both sides, and the jumps from country to country were well handled. The underlying theme of the rising right-wing and disgruntled young men felt topical, but the action wasn't quite what I was hoping for. The story was, on the whole though, nicely paced and easy to read.

Overall, this fell a bit flat for me and the ending was far too anti-climatic given the stakes, with it feeling a little rushed. The epilogue was great though but as a spy thriller, I didn't feel as thrilled as I should've felt and I came away feeling a little disappointed.

A huge thank you to Netgalley, Penguin Randomhouse and Michael Joseph for the ARC

[Louise Wilson · Rating 4 out of 5]

A DYING RUSSIAN SCIENTIST confesses to his children what he did as a

Stella McRae had left MI6 and had set up her own private intelligence company, and Hoss was her only employee. She is contacted by an old Secret Service friend about a terrorist plot to destroy the lives of innocent people across Europe. With not a lot to go on, Stella finds herself in a race against time to stop the terrorist plot before it's too late.

This story is graphic, gripping and very well-written. I liked the author's writing style. It's action-packed and you can't trust anyone. We travel from country to country during the investigation. I liked the main characters, they were strong and well-developed. I quite enjoyed this spy thriller.

Published 28th May 2026

I would like to thank #NetGalley #MichaelJoseph #PenguinRandomHouse and the author #CJMerritt for my ARC of #Octagon in exchange for an honest review.

[Donna Morfett · Rating 5 out of 5]

Ive spent my whole day almost in the company of Stella and Tommy as they barrel across Europe, in pursuit of some stolen Uranium and uncovering a huge terrorist plot.
It starts off in the UK, Stella is ex MI6, she left under a cloud and has now set up her own intelligence agency, assisted by the brilliant Hoss.
When she receives a duress code, she knows she must act, and the only person who she trusts to be by her side is ex SAS man Tommy.
I like Stella who was strong and powered through some tough situations. Tommy was complex, with some issues in the background, showing he was a softie, not just a muscly meathead.
Hoss was the frustrated junior, stuck behind but actually gets some incredible intel. He is also responsible for one of my favourite moments involving his mums make up and her response.
The action is intense, and it does not let up at all, its a fairly complex plot but easy to follow and I loved it.
I hope there is more to come from Stella, Tommy and Hoss.

[Bob Galloway]

An epic caper with three well drawn main characters involved in a travelog of scenarios all over western Europe.The bad guys grab the attention of our three good guys with a bizarre ritual murder which soon mutates into a planned spectacular terrorism event which the good guys have to thwart.
Good plausible plot flow and plenty of well defined action and excitement.
The three main characters are interesting and I suspect we might see them again soon.Stella,the female lead seemed a bit too girly for a trained MI6 field agent and Tommy the male lead will surely benefit from his PTSD treatment before his next outing.
Comparison with the Pilgrim book is unfair for this novel stands on it's own merit,recommended.

[Ridgerunner · Rating 4 out of 5]

I think that the fact that the mysterious head of an evil organisation is called “ the master” tells you a lot about this book. Hard done by ex SIS officer teaming up with an ex SAS soldier to try to thwart a dastardly plan to totally disrupt Europe.
The action was not too ridiculously unbelievable as can sometimes be the case but still there is a fairly high body count. Stella is the more likeable of the main characters as the ex intelligence officer while Tommy is the less complex super capable ex soldier.
But the book is all about action and the intensity is kept high throughout the book making for an easy quick read.
Thanks to NetGalley and Random House for the ARC.

[Cassie · Rating 3 out of 5]

I really enjoyed the opening chapters, especially the feistiness of Stella McRae the former MI6 officer – so nice to have a female protagonist. The premise and plotting felt very current. The story moved quickly and covered a number of European countries, with the trusty office-bound assistant providing input as the plot unfolds.
At some point the exploits of Stella and her bodyguard spilled over from great heroic drama to impossible to believe.
An interesting gallop through modern day politics.

I received a free copy of this novel from NetGalley in return for an honest review.

[Jane Hunt · Rating 4 out of 5]

A deathbed confession sets the scene for this compelling, gritty political thriller. Stella, a former MI6 operative now in the private sector, receives a cryptic call for help from an old colleague. His unexpected death prompted her to follow his leads, and so begins a story of terrifying discoveries, political intrigue, and courageous action by the protagonists. I appreciated the fast-paced action, the clever plotting and the authentic settings. It is immersive and keeps you turning the pages to its impactful conclusion.
I received a copy of this book from the publisher.

[Rachel · Rating 4 out of 5]

3.5 stars rounding up. A murdered spy. A ritual killing. A continent in peril.... This international spy thriller that reads like a movie in my head. Think a Dan Brown puzzle hunt meets the gritty, messy spycraft of Slow Horses. Huge compliment. It gets badass and graphic as they chase across Europe, but that's what kept me addicted. The author’s background is fascinating, which is what made me curious about how he would pull this off. It is a good ride. Bonus points for the coordinates at the top of each chapter. I geeked out looking those up a few times.

[Jason · Rating 5 out of 5]

Topical, fast paced thriller with strong main characters up against the clock as they seek to prevent a series of terrorist attacks in Europe.

Recalls Robert Ludlum at his peak, with the dry humour and espionage background of Mick Herron's Slough House novels.

Roll on the next book!