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Sentinel (Voyager) Paperback – September 16, 2020
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The Voyager story continues...
Four years have passed since Voyager One sent back chilling photos of a spaceship from deep in interstellar space.
A shocked world prepared to meet the Visitors, but terrorism, pandemics, and global political turmoil have now consumed it. Discredited as a hoax, the Visitors have faded from public attention.
But the powerful global conspiracy known as the Triumvirate is behind much of the chaos. Creating a screen of subterfuge and misdirection, they prepare a clandestine welcome for the Visitors, whose origins may be more sinister than the aliens of popular fiction.
Standing in their way are the few brave men and women who foiled the Triumvirate’s last attempt to upset the world’s fragile balance of power:
Former FBI agent Brad Barnes leads Sentinel, a private intelligence and counter-terrorism operation founded in the wake of the Triumvirate’s last deadly plot.
Alex Ephraim – the former Triumvirate assassin known as Mirage – is Sentinel’s major weapon against terror.
Matt Ramprakash, former airline pilot and now an officer of the British intelligence agency MI5, is embroiled in a deadly standoff when an airliner is hijacked.
Callie Woolf, once the project manager of the Voyager mission, struggles against the sceptical government’s bureaucracy to continue the search for the elusive Visitors as her time and funding runs out.
Sentinel is the only organisation capable of taking the fight to the Triumvirate’s door – flexible, unorthodox well-funded and free of government red tape.
But as they pursue the Triumvirate from the streets of London to the wild, deadly wastes of Antarctica, Brad will need Matt and Callie’s help to stop the Triumvirate, which has its own plans for putting Sentinel – and especially Alex – out of the picture for good…
Sentinel is the pulse-pounding second instalment in the Voyager trilogy by Carl Rackman
Praise for Carl Rackman’s Voyager:
‘This tautly constructed suspense novel kept me turning the pages’ – RA Book Review Team
‘Carl Rackman has done it again.’ – Between The Lines Book Review
‘Keeps you reading non stop enraptured’ – Odysseus, Amazon reviewer
‘Voyager is a modern suspense thriller with unexpected twists that keep you guessing and engaged to the end.’ – Baldrick, Amazon reviewer
- Print length292 pages
- LanguageEnglish
- Publication dateSeptember 16, 2020
- Dimensions6 x 0.73 x 9 inches
- ISBN-13979-8675821303
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Product details
- ASIN : B08JF2BKT6
- Publisher : Independently published
- Publication date : September 16, 2020
- Language : English
- Print length : 292 pages
- ISBN-13 : 979-8675821303
- Item Weight : 15.3 ounces
- Dimensions : 6 x 0.73 x 9 inches
- Book 2 of 2 : Voyager
- Best Sellers Rank: #10,361,524 in Books (See Top 100 in Books)
- #9,428 in Technothrillers (Books)
- #40,197 in Science Fiction Adventures
- Customer Reviews:
About the author

Hi! I'm Kurt Rackman, a British former airline pilot turned author. I spent my working life travelling the world and this has given me a keen interest in other people and cultures. I've drawn on my many experiences for my writing.
I write suspense thrillers with a grounded science-fiction theme. I like reading novels that feature atmospheric locales and I enjoy complex, absorbing storylines combined with rich, believable characters, so that's the sort of fiction I write. I try to create immersive worlds for the reader to explore, and characters who are more than just vehicles for the story.
I come from a naval military background and have held a lifelong interest in military history and seafaring - all my books usually contain some of these elements!
I hope you'll enjoy my books and leave reviews. I try to personally thank reviewers if they've particularly enjoyed my books.
Find out more about me, my writing and my upcoming books at rackmanbooks.com. You can usually find me on Twitter - @KurtRackman - I'd love to link up with you as followers.
Thanks for looking,
KR
Customer reviews
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- Reviewed in the United States on September 29, 2020This series was recommended to me by a friend and I'm so glad! Thoroughly enjoyed it this 2nd book in the series. Great action and gripping plotline. Hope there is a 3rd!
- Reviewed in the United States on November 19, 2020I will confess I am a fan of Carl Rackman’s books but somehow missed the first book in this series, Voyager. Nevertheless, I plowed ahead and discovered that the author covered enough of the high points from Voyager that I could hit the ground running. I was not disappointed.
Four years have passed since Voyager One sent back chilling photos of a spaceship from deep in interstellar space. However, with terrorism, pandemics and political turmoil consuming the news, the story faded to the back page and the public has accepted it as a hoax. All but the Triumvirate, a global and powerful conspiracy that has inserted itself into the highest levels of various governments. They have created a wall of subterfuge so they themselves can welcome the Visitors, the occupants of the spaceship, who are coming with sinister plans.
Countering the Triumvirate are the strong characters typical of Rackman’s writing: Matt Ramprakash, former airline pilot and now an officer of the British intelligence agency MI5; his wife, Callie Woolf, who once headed the Voyager One mission and who believes that the spaceship is not a hoax; former FBI agent Brad Barnes who now leads Sentinel, a private intelligence and counter-terrorism operation founded to counter the Triumvirate; and Alex Ephraim, a superhuman soldier, thought to be genetically engineered, and a former Triumvirate assassin who has switched sides to join Sentinel.
The story opens a little slowly, which is where I think it could have been improved, but then starts to pick up speed until by the end, the reader is reading and flipping pages as fast as possible. The action scenes are meticulously plotted and easy to visualize and employ incredible technology. From a diversionary airplane hijacking to action on the icy cold and barren reaches of Antarctica, this suspense thriller pulls you in and then delivers a solid punch with a science fiction twist, leading directly to a third book in this series. Which I await.
This is a cracking good read.
- Reviewed in the United States on October 19, 2020This is the sequel to Rackman's Voyager, which I haven't read, but it totally works as a stand-alone; there is enough information about what happened before, without long, tedious explanations. Could actually be presented as a masterclass in how to do this!
Former pilot Matt Ramprakash is now an aviation expert for M15, and, along with many from other government agencies, etc, awaits assitance from anti-terrorism body Sentinel in taking action on a hijacked plane - but who are the hijackers? The discovery that his old enemy, the Triumvirate, are involved, leads him to Antarctica, along with Sentinel, his wife - and Mirage, a 'supersoldier' who has been genetically engineered - or has she?
As I was reading this, it occurred to me that Carl Rackman has invented his own genre - seemingly earthbound thrillers that end up being a bit paranormal, without it seeming weird. Works very well! The amount of research that has gone into this book is evident; it's highly professional, extremely well-written, and should appeal to anyone who loves an intricate government thriller. With some alien stuff thrown in. I read at the end that a third book is planned - I would love to see some of it from the point of view of the Visitors. The ending was one of the best I have seen for this type of book—the sort that makes you want to open the next instalment immediately.
I felt it could have been edited down a little in places, with less factual detail and fewer conversational exchanges, to tighten up the pace, but that could be just personal preference; it's a smart, intelligent novel of which the author should be most proud. And I know it's a cliché, but it really would make a fabulous TV series!
- Reviewed in the United States on September 25, 2020I simply could not get into this book and gave up at 5%. IMO this seems to be typical of too many of these formulaic series...first book is good and it's downhill from there.
Top reviews from other countries
- Mac WoodReviewed in the United Kingdom on October 3, 2020
5.0 out of 5 stars He keeps getting better
It's good to be reading another Carl Rackman book. He continues to draw you into his world until your gripped. It's taken me longer to finish Sentinel than previous stories, perhaps because I'm older, because although these are works of fiction, the world you are enticed into becomes a new reality and the tension builds with every page turned.
I won't disect the story, but suffice to say whatever money you pay for your copy it'll be money well spent. Hurry up with book 3!
- Pete ThomasReviewed in Australia on January 16, 2021
5.0 out of 5 stars Fast paced action
Another great book. Reminds me of the early work by Matthew Riley. Fast paced non stop action with enjoyable characters.
- Terry TylerReviewed in the United Kingdom on October 19, 2020
4.0 out of 5 stars 4.5* Exciting Goverment-SciFi Thriller
This is the sequel to Rackman's Voyager, which I haven't read, but it totally works as a stand-alone; there is enough information about what happened before, without long, tedious explanations. Could actually be presented as a masterclass in how to do this!
Former pilot Matt Ramprakash is now an aviation expert for M15, and, along with many from other government agencies, etc, awaits assitance from anti-terrorism body Sentinel in taking action on a hijacked plane - but who are the hijackers? The discovery that his old enemy, the Triumvirate, are involved, leads him to Antarctica, along with Sentinel, his wife - and Mirage, a 'supersoldier' who has been genetically engineered - or has she?
As I was reading this, it occurred to me that Carl Rackman has invented his own genre - seemingly earthbound thrillers that end up being a bit paranormal, without it seeming weird. Works very well! The amount of research that has gone into this book is evident; it's highly professional, extremely well-written, and should appeal to anyone who loves an intricate government thriller. With some alien stuff thrown in. I read at the end that a third book is planned - I would love to see some of it from the point of view of the Visitors. The ending was one of the best I have seen for this type of book—the sort that makes you want to open the next instalment immediately.
I felt it could have been edited down a little in places, with less factual detail and fewer conversational exchanges, to tighten up the pace, but that could be just personal preference; it's a smart, intelligent novel of which the author should be most proud. And I know it's a cliché, but it really would make a fabulous TV series!
- John CumminsReviewed in the United Kingdom on September 19, 2022
5.0 out of 5 stars excellent sequel
excellent sequel, can't wait for the next instalment