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Sam Reilly #20
The Obsidian Chamber
In A.D. 79, Mount Vesuvius erupted and a small girl raced for her life along the cobblestone streets of Pompeii. She needed to survive. She needed to tell someone what she had done so that it could never happen again…
In present day, while Sam Reilly is on a mission to locate the long-lost shipwreck of legendary explorer Earnest Shackleton, a strange code begins to circulate on the internet. It purports to have the answers to some of the world’s most complex engineering and algorithmic problems.
The US government’s brightest minds are racing to be the first to break what has the potential to be the most powerful code on Earth.
And the most dangerous.
In present day, while Sam Reilly is on a mission to locate the long-lost shipwreck of legendary explorer Earnest Shackleton, a strange code begins to circulate on the internet. It purports to have the answers to some of the world’s most complex engineering and algorithmic problems.
The US government’s brightest minds are racing to be the first to break what has the potential to be the most powerful code on Earth.
And the most dangerous.
268 pages, Kindle Edition
First published January 6, 2020
424 people are currently reading
306 people want to read
About the author
Christopher Cartwright
73 books250 followersChristopher Cartwright writes spellbinding mysteries and suspense novels. Often with a backdrop of ocean adventure. Born in 1983, he has a background as a paramedic, and is an avid sailor and SCUBA diver.
He holds degrees in paramedics, nursing and emergency management.
Chris currently lives in Sydney with his wife and two children.
He holds degrees in paramedics, nursing and emergency management.
Chris currently lives in Sydney with his wife and two children.
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Displaying 1 - 30 of 52 reviews
January 24, 2020
I really enjoy this series of books they are easy to read and
enjoyable. I wonder if any other regulars of these books have
felt or noticed that Sam seems to be getting a bit harder and more ruthless
as time has gone on. Or is this just me
enjoyable. I wonder if any other regulars of these books have
felt or noticed that Sam seems to be getting a bit harder and more ruthless
as time has gone on. Or is this just me
October 1, 2025
Brief synopsis from the book cover:
In A.D. 79, Mount Vesuvius erupted and a small girl raced for her life along the cobblestone streets of Pompeii. She needed to survive. She needed to tell someone what she had done so that it could never happen again…
In present day, while Sam Reilly is on a mission to locate the long-lost shipwreck of legendary explorer Earnest Shackleton, a strange code begins to circulate on the internet. It purports to have the answers to some of the world’s most complex engineering and algorithmic problems.
The US government’s brightest minds are racing to be the first to break what has the potential to be the most powerful code on Earth.
And the most dangerous.
My rating:
Plot: 4 out of 5 stars
Writing: 4 out of 5 stars
Character development: 4 out of 5 stars
Overall: 4 out of 5 stars
Recommended for readers of:
Action and Adventure
Review:
This Sam Reilly adventure is a masterclass in fast-paced storytelling. From the ash-choked streets of ancient Pompeii to the icy depths of Shackleton’s lost expedition, this novel delivers a whirlwind of action, mystery, and high-stakes intrigue.
The plot is pure adrenaline: a cryptic code surfaces online, promising to unlock the secrets of the universe—or unleash chaos. As governments scramble to crack it, Reilly dives headfirst into a globe-spanning quest that fuses historical secrets with cutting-edge technology.
Expect larger-than-life characters who leap off the page. Sam Reilly is the quintessential action hero—brilliant, fearless, and always one step ahead. The supporting cast is equally vivid, each with their own quirks and motivations that keep the tension crackling.
This is classic action and adventure; entertaining, cinematic, and packed with twists. If you love your thrillers with ancient mysteries, modern tech, and a dash of danger, this one’s a must-read.
In A.D. 79, Mount Vesuvius erupted and a small girl raced for her life along the cobblestone streets of Pompeii. She needed to survive. She needed to tell someone what she had done so that it could never happen again…
In present day, while Sam Reilly is on a mission to locate the long-lost shipwreck of legendary explorer Earnest Shackleton, a strange code begins to circulate on the internet. It purports to have the answers to some of the world’s most complex engineering and algorithmic problems.
The US government’s brightest minds are racing to be the first to break what has the potential to be the most powerful code on Earth.
And the most dangerous.
My rating:
Plot: 4 out of 5 stars
Writing: 4 out of 5 stars
Character development: 4 out of 5 stars
Overall: 4 out of 5 stars
Recommended for readers of:
Action and Adventure
Review:
This Sam Reilly adventure is a masterclass in fast-paced storytelling. From the ash-choked streets of ancient Pompeii to the icy depths of Shackleton’s lost expedition, this novel delivers a whirlwind of action, mystery, and high-stakes intrigue.
The plot is pure adrenaline: a cryptic code surfaces online, promising to unlock the secrets of the universe—or unleash chaos. As governments scramble to crack it, Reilly dives headfirst into a globe-spanning quest that fuses historical secrets with cutting-edge technology.
Expect larger-than-life characters who leap off the page. Sam Reilly is the quintessential action hero—brilliant, fearless, and always one step ahead. The supporting cast is equally vivid, each with their own quirks and motivations that keep the tension crackling.
This is classic action and adventure; entertaining, cinematic, and packed with twists. If you love your thrillers with ancient mysteries, modern tech, and a dash of danger, this one’s a must-read.
June 30, 2022
I'm not sure how this ended up on my kindle. I had to have bought it because Chirp books are never free, but it's not the type of book I normally read. It was interesting, and I've never read any of the Sam Reilly and had no trouble following the characters. There's a lot of explanation - Shackelton, how hovercrafts work...I had trouble believing a Roman ship from the first century made it into Lake Erie and how the faces looked like people in the 21st century. One thing I did like, unlike the author, Dan Brown, Mr. Cartwright gifted all his characters with intelligence and others besides Sam could explain things. I don't plan on reading any more in this series.
February 5, 2025
Review of book.
Another fantastic book! Full of action, twists and deception. Sam and the rest of the crew are busy trying to solve mysteries and save people and the environment. The ending is unbelievable! A boy plays a crucial role. You will not believe what happens at the end. I was stunned! The next book will no doubt raise more questions than answers. It is a good thing that there are thirty-one books in the series so far. I imagine that a lot of questions will be answered in the next book. This is truly a great series.
Another fantastic book! Full of action, twists and deception. Sam and the rest of the crew are busy trying to solve mysteries and save people and the environment. The ending is unbelievable! A boy plays a crucial role. You will not believe what happens at the end. I was stunned! The next book will no doubt raise more questions than answers. It is a good thing that there are thirty-one books in the series so far. I imagine that a lot of questions will be answered in the next book. This is truly a great series.
March 23, 2025
A little too many technical details for me
What a great yarn of a story. For me, the technical details, such as all the details about the different types of craft/vehicles and how they were powered what they could and couldn’t do—was a little much. Then the Tesla, and every finite detail. Just too much. Don’t get me wrong… as a seasoned technical writer I like to learn how things work, but there’s a point where overkill spoils the story.
Jordan seemed to be abandoned at the end. What happened to him?
What a great yarn of a story. For me, the technical details, such as all the details about the different types of craft/vehicles and how they were powered what they could and couldn’t do—was a little much. Then the Tesla, and every finite detail. Just too much. Don’t get me wrong… as a seasoned technical writer I like to learn how things work, but there’s a point where overkill spoils the story.
Jordan seemed to be abandoned at the end. What happened to him?
March 29, 2020
Another Sam Reilly adventure has him following up on Shackleton's cruise to the South Pole in search of information on the breaking the code on the location of the "obsidian chamber" and it turns that he is not the only one searching for it. Action, danger, a new hunt, new clues and more conflict with other searchers, more clues in code and a dire warning if certain actions are taken. Good escapism reading for these shut in days.
July 3, 2020
The Obsidian Chamber (Sam Reilly #20), my twentieth read from author Christopher Cartwright & the twentieth book in the highly entertaining Sam Reilly series. A well-written rollicking thriller with captivating & well-developed main characters. The worst thing about a Sam Reilly book is waiting for the next book to be done. Reminds me of the writings of Steve Berry, Dan Brown & James Rollins. Next up is Shangri-La (Sam Reilly #21). (RIP Marley January 20, 2014 - July 24, 2018).
May 8, 2023
Fast Paced and Exciting Adventure
Christopher's Sam Reilly books are enthralling and this is no different. From Oregon to Pompei, the adventure never looses pace or ever ceases to thrill. The usual gang are all present and I could barely put this down. Great details which help make it a great story. I always learn a lot reading these stories which I enjoy. I'd highly recommend this book.
Christopher's Sam Reilly books are enthralling and this is no different. From Oregon to Pompei, the adventure never looses pace or ever ceases to thrill. The usual gang are all present and I could barely put this down. Great details which help make it a great story. I always learn a lot reading these stories which I enjoy. I'd highly recommend this book.
August 17, 2023
This one had one of my favorite prologues. I think the ending location was disappointing, but I really liked the build up to overarching plot line elements. I was a bit disappointed with the ultimate direction Cartwright took, but I also understand it. I’m hoping later books will help balance it all back out. I didn’t love the character that was introduced, but again, it made sense. I’ll wait to make any harsh judgements until later in the series
April 26, 2020
Another excellent read by Christopher Cartwright!
Book 20 in the Sam Reilly series is as good as book 1. Unlike other series that get dull and repetitive, this series gets better and better. It will be hard to wait another few days for book 21. Please keep this series alive. Thank you for the hours of diversion from life and immersion in an adventure.
Book 20 in the Sam Reilly series is as good as book 1. Unlike other series that get dull and repetitive, this series gets better and better. It will be hard to wait another few days for book 21. Please keep this series alive. Thank you for the hours of diversion from life and immersion in an adventure.
June 21, 2021
Secrets revealed
The plan to bring the alien world to earth is finally uncovered as further archaeological discoveries are made by Sam and his team. The story is typical of the Sam Reilly series in that it is full on action from start to finish. Well written with several characters taken from ancient history. Who would have thought history could be so much fun!
The plan to bring the alien world to earth is finally uncovered as further archaeological discoveries are made by Sam and his team. The story is typical of the Sam Reilly series in that it is full on action from start to finish. Well written with several characters taken from ancient history. Who would have thought history could be so much fun!
March 3, 2023
History Repeats Itself
What a mind that can create such a lengthy thriller series. Incredible! And so true to life with all the unthinkable happenings suddenly turning up on our nightly news years after Cartwright has written about them as fiction. Surprising a a little creepy. I’ve got to find out what happens next!
What a mind that can create such a lengthy thriller series. Incredible! And so true to life with all the unthinkable happenings suddenly turning up on our nightly news years after Cartwright has written about them as fiction. Surprising a a little creepy. I’ve got to find out what happens next!
October 2, 2024
I do like fantasy and science fiction, they are my favorite genres. This book and author tread the line between “realistic” thriller and fantastic fiction too closely. Ian’s to believe that the action is taking place in my world, but the action is too fantastic to be believable. Still three stars for being a fun, easy read.
June 9, 2020
Interesting
This book took a twist I wasn't expecting. I not sure where the story is going. I originally thought these books were going to be more along the lines of archeological searches but not so.
This book took a twist I wasn't expecting. I not sure where the story is going. I originally thought these books were going to be more along the lines of archeological searches but not so.
March 5, 2021
Sam Reilly surprised me again.
Another winner. Can’t wait to start the next book!!!
Christopher Cartwright and Sam Reilly are a perfect combination. Hopefully they will be around for a long time
Another winner. Can’t wait to start the next book!!!
Christopher Cartwright and Sam Reilly are a perfect combination. Hopefully they will be around for a long time
March 24, 2022
adventure
High octane adventure with mysteries, puzzles and twists. The crew has smarts and money for all sorts of interesting equipment to make the books exciting and interesting
High octane adventure with mysteries, puzzles and twists. The crew has smarts and money for all sorts of interesting equipment to make the books exciting and interesting
April 19, 2022
The life of Reilly
Another fantastic book, love following the escapades of Sam Reilly. You never know where he's going to end up next. All of Christopher 's books are full of spellbinding action. Looking forward to reading more.
Another fantastic book, love following the escapades of Sam Reilly. You never know where he's going to end up next. All of Christopher 's books are full of spellbinding action. Looking forward to reading more.
May 3, 2022
Another thrill ride
Once again Sam Reilly is in the middle of history searching for the truth and a way to save humanity. Some questions get answered but more are discovered. A fast and easy read.
Once again Sam Reilly is in the middle of history searching for the truth and a way to save humanity. Some questions get answered but more are discovered. A fast and easy read.
October 14, 2022
fantastic book! couldn’t put it down. But……?
Full of action and suspense from page 1 to the end. But…
There is always a question left over at the end to be answered that carries you over to the next book in the series. Well, it’s on to the next book. I need answers!!!
Full of action and suspense from page 1 to the end. But…
There is always a question left over at the end to be answered that carries you over to the next book in the series. Well, it’s on to the next book. I need answers!!!
October 15, 2022
Unbelievable yet compelling
I have read many Sam Riley e-books before so I'm used to the improbable and the impossible happening. Sam Riley is like a human action hero. Written by an exceptional author makes this unlikely journey and enjoyable one.
I have read many Sam Riley e-books before so I'm used to the improbable and the impossible happening. Sam Riley is like a human action hero. Written by an exceptional author makes this unlikely journey and enjoyable one.
November 15, 2022
Good syfy!
The book was well written and the characters fleshed out well. Overall, I enjoyed the book. Close to the end the grill being saved was almost unbelievable, but it allowed the series to continue.
The book was well written and the characters fleshed out well. Overall, I enjoyed the book. Close to the end the grill being saved was almost unbelievable, but it allowed the series to continue.
February 11, 2023
Book 20
Interesting book in the search for the builders. Mr. Cartwright takes the reader for a ride in his books, lot of different sites and explained slot of information for autism.
Interesting book in the search for the builders. Mr. Cartwright takes the reader for a ride in his books, lot of different sites and explained slot of information for autism.
April 4, 2023
Gripping read from start to finish!
Fast moving plot
Surprising twists and excellent characters with an ending that leaves you wanting more and searching for the next book in the series to read.
Fast moving plot
Surprising twists and excellent characters with an ending that leaves you wanting more and searching for the next book in the series to read.
January 15, 2024
I read (or tried to) Sam Reilly #1 and I wanted to see if 20 books later the author had improved. But unfortunately, it's just as bad, at least there's constance in his work. The writing is beyond poor. I forced myself to finish the first chapter but that's as far as I could go.
July 7, 2020
Great read...
I really enjoyed this book! As I have all the books in this series! I like the fact that I learn from them as well!
I really enjoyed this book! As I have all the books in this series! I like the fact that I learn from them as well!
January 13, 2021
Always enjoy the Sam Reilly books, he is a no holds barred type of guy & action all the way!
May 7, 2021
The Sam Reilly series is a fun read
September 2, 2021
Wow
This is such an adrenal rush as Sam once again gets into a life threatening situations of good versus evil and his friends and colleagues again help to save humanity.
This is such an adrenal rush as Sam once again gets into a life threatening situations of good versus evil and his friends and colleagues again help to save humanity.
June 29, 2022
Amazing!
I am becoming a Christopher Cartwright addict! I have never read so many books in order like this! He's the master of cliff hangers! THE OBSIDIAN CHAMBER is excellent! The adventures just keep rolling on!
I am becoming a Christopher Cartwright addict! I have never read so many books in order like this! He's the master of cliff hangers! THE OBSIDIAN CHAMBER is excellent! The adventures just keep rolling on!
October 17, 2022
The Obsidian Chamber was very good action reading. It kept me reading every minute that I could get.
Displaying 1 - 30 of 52 reviews