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John Decker #6
Black Tide
A secret mission. A horror beyond imagination.
In the last months of World War Two, the German Navy premiered a new and terrifying weapon. A submarine of incredible range that could strike anywhere, anytime. And it did, prowling the shipping lanes night and day, and striking fear into the Allies. It was just what Hitler needed to turn the tide of war.
Until it disappeared without a trace.
Now, more than seven decades later, the wreck of a previously unknown U-Boat has been found off the South American coast. A submarine so well preserved that it shouldn’t exist. Eager to learn its secrets, a team of marine archaeologists arrive at a unique seafloor habitat to study the wreck up close. But something has survived on the empty sub. A dark and terrifying presence.
Answering the panicked researcher’s distress call, CUSP sends John Decker to assess the situation. What he finds on the cold and lonely ocean floor is unlike anything he has seen before. A horror from the blackest days of the war. And it doesn’t want them to leave. At least, not alive.
This is book six in the John Decker series, but it can be read as a standalone novel.
If you are a fan of James Rollins, Douglas Preston, Lincoln Child, and Steve Alten, you will love the John Decker series.
In the last months of World War Two, the German Navy premiered a new and terrifying weapon. A submarine of incredible range that could strike anywhere, anytime. And it did, prowling the shipping lanes night and day, and striking fear into the Allies. It was just what Hitler needed to turn the tide of war.
Until it disappeared without a trace.
Now, more than seven decades later, the wreck of a previously unknown U-Boat has been found off the South American coast. A submarine so well preserved that it shouldn’t exist. Eager to learn its secrets, a team of marine archaeologists arrive at a unique seafloor habitat to study the wreck up close. But something has survived on the empty sub. A dark and terrifying presence.
Answering the panicked researcher’s distress call, CUSP sends John Decker to assess the situation. What he finds on the cold and lonely ocean floor is unlike anything he has seen before. A horror from the blackest days of the war. And it doesn’t want them to leave. At least, not alive.
This is book six in the John Decker series, but it can be read as a standalone novel.
If you are a fan of James Rollins, Douglas Preston, Lincoln Child, and Steve Alten, you will love the John Decker series.
334 pages, Kindle Edition
First published February 12, 2021
669 people are currently reading
258 people want to read
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Displaying 1 - 30 of 83 reviews
October 6, 2024
Boring Tide.
John Decker and the crew of Habitat 1 are sitting on the bottom of the sea. They are there to do some research on a submarine that has been on the bottom of the ocean for 82 years.
There is something special about the sub. It doesn’t look 82 years old. In fact, it doesn’t look as if it has aged at all. What kind of technology were the German military using during WWII?
Decker also have to find an answer to another question. Who’s behind the attacks on members of the crew? Someone has attacked Lauren and Mac and someone has been murdered.
Things are getting scary. It is time to get off of Habitat 1!
Four stars. ✨✨✨✨
John Decker and the crew of Habitat 1 are sitting on the bottom of the sea. They are there to do some research on a submarine that has been on the bottom of the ocean for 82 years.
There is something special about the sub. It doesn’t look 82 years old. In fact, it doesn’t look as if it has aged at all. What kind of technology were the German military using during WWII?
Decker also have to find an answer to another question. Who’s behind the attacks on members of the crew? Someone has attacked Lauren and Mac and someone has been murdered.
Things are getting scary. It is time to get off of Habitat 1!
Four stars. ✨✨✨✨
May 2, 2025
⭐️⭐️ - Audiobook 🎧
This one was a little far-fetched, even for me, and that’s saying something.
This one was a little far-fetched, even for me, and that’s saying something.
July 15, 2024
This book was so entertaining! One of my favorites of the series so far, I could tell a lot went into researching and writing this. If you're a fan of WWII history, submarines/boats, and STEM careers, this is for you. Decker is back with CUSP for an undersea adventure. A team has discovered a WWII era submarine on the ocean floor with a lot going on; it's completely sealed and airtight, there are no crew bodies, and...it looks brand new, despite being sunk for over 80 years. Odd? Yes. Supernatural? Possibly.
The research crew has set up a base camp on the bottom of the ocean and is splitting time between their station and the submarine as they study it. But spooky things start happening, and the crew of scientists isn't ready to admit they may be experiencing ghost encounters. Enter Decker. John is way outside of his comfort zone, but is a gungho guy nonetheless, so he ventures forward. As he meets the crew and starts to do some sleuthing, he's more and more puzzled. Some of the evidence points to a person...but other evidence points to the supernatural.
This started out a bit slow for me, but I really dug in once the scene was painted. I was so curious about who/what the bad guy was, and I figured out one half by the end. It was so interesting to learn about the mechanics, and the logistics of living underwater for any given period of time (hygiene on WWII era subs - YUCK) as well as meeting new characters and back stories. I'm having such a fun time with this series!
The research crew has set up a base camp on the bottom of the ocean and is splitting time between their station and the submarine as they study it. But spooky things start happening, and the crew of scientists isn't ready to admit they may be experiencing ghost encounters. Enter Decker. John is way outside of his comfort zone, but is a gungho guy nonetheless, so he ventures forward. As he meets the crew and starts to do some sleuthing, he's more and more puzzled. Some of the evidence points to a person...but other evidence points to the supernatural.
This started out a bit slow for me, but I really dug in once the scene was painted. I was so curious about who/what the bad guy was, and I figured out one half by the end. It was so interesting to learn about the mechanics, and the logistics of living underwater for any given period of time (hygiene on WWII era subs - YUCK) as well as meeting new characters and back stories. I'm having such a fun time with this series!
January 26, 2025
Being stuck on the ocean with some type of creature.... absolutely not.
I'll never go on a cruise ship, mainly because I can't take my dog (and I'm extremely paranoid about if the ship sinks and them not letting her off the boat because I will die for her.. not that I've thought of that time and time again anytime I see a Carnival commercial 🫠👀) and she goes literally, everywhere with me.
I'll never go on a cruise ship, mainly because I can't take my dog (and I'm extremely paranoid about if the ship sinks and them not letting her off the boat because I will die for her.. not that I've thought of that time and time again anytime I see a Carnival commercial 🫠👀) and she goes literally, everywhere with me.
August 15, 2022
A rip roaring adventure!
This was an enjoyable and fast moving tale of extra terrestrial technology, captured and used by the Germans during the second world war. Imagine UFO technology being inserted into a 1940s submarine. What would be the result? Perhaps something along the lines of the alleged US experiments concerning the warship Philadelphia. Pre Roswell incidents resulting in technology recovered that, at the time, could not accurately be reverse engineered. Hold onto your hat, suspend belief and just enjoy the tide.
This was an enjoyable and fast moving tale of extra terrestrial technology, captured and used by the Germans during the second world war. Imagine UFO technology being inserted into a 1940s submarine. What would be the result? Perhaps something along the lines of the alleged US experiments concerning the warship Philadelphia. Pre Roswell incidents resulting in technology recovered that, at the time, could not accurately be reverse engineered. Hold onto your hat, suspend belief and just enjoy the tide.
January 28, 2025
(3,5 ☆) Brukar ledsna på såna här serier efter ett tag men har hittills inte tröttnat på Anthony M. Strong. Action, äventyr, häftiga miljöer, plotdriven spänning, diverse monster och en hel del humor (delvis frivillig men kanske mest ofrivillig ändå). Kan inte bli annat än kul, faktiskt. Letar du däremot efter intressanta karaktärsutvecklingar och djupa teman kanske du ska leta vidare :) Får se om jag lyckas ta mig igenom resterande fem delar.
February 5, 2022
My favourite Decker book since the first one! I read this in one go! I continue to enjoy this series, despite the non-development of John's personal life, there really needs to be more balance there. Upwards and onwards to the next novel in the series.
November 1, 2024
Loved it!
If you like thrillers with a little paranormal, you should read this series. I'm always looking forward to the next book. Needs a final proofreading, though.
If you like thrillers with a little paranormal, you should read this series. I'm always looking forward to the next book. Needs a final proofreading, though.
February 18, 2021
ADDICTIVE READING!!!
This is the latest book by Anthony M Strong in the John Decker series, briefly the story is about a submarine in the last months of World War Two, the German Navy premiered a new and terrifying weapon. A submarine of incredible range that could strike anywhere, anytime. And it did, prowling the shipping lanes night and day, and striking fear into the Allies. It was just what Hitler needed to turn the tide of war.
Until it disappeared without a trace!!
I have read all the books in this series so far and all have been amazingly addictive reads. This new book as usual the author manages to hold my attention throughout from the first page to the very last, I hear myself saying just one more chapter, one more then another.
As I read the book it is like a motion picture running in my head due to the descriptions and writing. Absolutely love this series it’s so addictive I never want the story to end or put the book down. Patiently waiting for the next book in the John Decker Series.
This is the latest book by Anthony M Strong in the John Decker series, briefly the story is about a submarine in the last months of World War Two, the German Navy premiered a new and terrifying weapon. A submarine of incredible range that could strike anywhere, anytime. And it did, prowling the shipping lanes night and day, and striking fear into the Allies. It was just what Hitler needed to turn the tide of war.
Until it disappeared without a trace!!
I have read all the books in this series so far and all have been amazingly addictive reads. This new book as usual the author manages to hold my attention throughout from the first page to the very last, I hear myself saying just one more chapter, one more then another.
As I read the book it is like a motion picture running in my head due to the descriptions and writing. Absolutely love this series it’s so addictive I never want the story to end or put the book down. Patiently waiting for the next book in the John Decker Series.
February 18, 2021
ADDICTIVE READING !!
This is the latest book by Anthony M Strong in the John Decker series, briefly the story is about a submarine in the last months of World War Two, the German Navy premiered a new and terrifying weapon. A submarine of incredible range that could strike anywhere, anytime. And it did, prowling the shipping lanes night and day, and striking fear into the Allies. It was just what Hitler needed to turn the tide of war.
Until it disappeared without a trace.
I have read all the books in this series so far and all have been amazingly addictive reads. This new book as usual the author manages to hold my attention throughout from the first page to the very last, I hear myself saying just one more chapter, one more then another.
As I read the book it is like a motion picture running in my head due to the descriptions and writing. Absolutely love this series it’s so addictive I never want the story to end or put the book down. Patiently waiting for the next book in the John Decker Series.
This is the latest book by Anthony M Strong in the John Decker series, briefly the story is about a submarine in the last months of World War Two, the German Navy premiered a new and terrifying weapon. A submarine of incredible range that could strike anywhere, anytime. And it did, prowling the shipping lanes night and day, and striking fear into the Allies. It was just what Hitler needed to turn the tide of war.
Until it disappeared without a trace.
I have read all the books in this series so far and all have been amazingly addictive reads. This new book as usual the author manages to hold my attention throughout from the first page to the very last, I hear myself saying just one more chapter, one more then another.
As I read the book it is like a motion picture running in my head due to the descriptions and writing. Absolutely love this series it’s so addictive I never want the story to end or put the book down. Patiently waiting for the next book in the John Decker Series.
December 21, 2022
Having read Anthony’s latest John Decker book, Fatal Crossing, the plot of which depends on what happened several books previous, I’ve decided to revisit some of these and offer up reviews.
Black Tide follows on from Whitechapel Rising with our hero being sent on a highly classified mission to an underwater science lab that’s researching a German U-Boat mysteriously abandoned without its crew on the sea bed but still in pristine condition - an underwater Marie Celeste!
This is the first book in the John Decker series that reads like a mature thriller. Suspense is amped up by the claustrophobia of murderous events taking place in an isolated environment at the bottom of the sea. As expected with a John Decker book there is more to events than meet the eye. Things aren’t quite right. Are there supernatural agencies at large?
To me this is the first in the John Decker series that feels like a proper, grown-up thriller. Although monstrous events happen it’s not the monster that’s the star. Instead it’s the people, the environment and the spooky U-Boat itself. On top of that there’s great, dynamic set pieces that’ll keep you on the edge of your seat.
So, don’t just sit there, grab this book and enjoy the ride. Black Tide can be read as a stand-alone.
Black Tide follows on from Whitechapel Rising with our hero being sent on a highly classified mission to an underwater science lab that’s researching a German U-Boat mysteriously abandoned without its crew on the sea bed but still in pristine condition - an underwater Marie Celeste!
This is the first book in the John Decker series that reads like a mature thriller. Suspense is amped up by the claustrophobia of murderous events taking place in an isolated environment at the bottom of the sea. As expected with a John Decker book there is more to events than meet the eye. Things aren’t quite right. Are there supernatural agencies at large?
To me this is the first in the John Decker series that feels like a proper, grown-up thriller. Although monstrous events happen it’s not the monster that’s the star. Instead it’s the people, the environment and the spooky U-Boat itself. On top of that there’s great, dynamic set pieces that’ll keep you on the edge of your seat.
So, don’t just sit there, grab this book and enjoy the ride. Black Tide can be read as a stand-alone.
February 21, 2021
There are some places that are just inherently scary. You have long, empty hotel corridors, you have creepy hospital basements and you have terrifying cabins in the woods. And now, thanks to this newest Decker book, you have submarines. Enclosed spaces with no way out, such as spaceships, have always had an inbuilt terror to them, hovering just below the surface. The author does a fantastic job of evoking that feeling of creeping dread and lurking horror from the moment you step aboard and plunge fathoms deep beneath the surface of the sea.
Once again, this author has managed to come up with a unique story, a blend of horror, mystery and thriller all rolled into one. The feeling of claustrophobia permeates the story and I still get chills thinking of some of the scenes in this book. As I always say, I can't wait for the next one in this series.
**I received an ARC copy of this book from the author. This review is strictly voluntary.**
Once again, this author has managed to come up with a unique story, a blend of horror, mystery and thriller all rolled into one. The feeling of claustrophobia permeates the story and I still get chills thinking of some of the scenes in this book. As I always say, I can't wait for the next one in this series.
**I received an ARC copy of this book from the author. This review is strictly voluntary.**
February 17, 2021
I received this book as an advance review copy and in return I am posting an honest review.
OK, regarding the previous John Decker book ,I knew I'd be interested because the main subject base, Jack the Ripper, is a fascination of mine. Black Tide deals with WW2 and the German Navy; couldn't be more different, and so, I thought, this new book wouldn't be of such interest to me. BUT this book had me enthralled from start to finish. I read the whole thing in one sitting, loved the mix of past and present and the very sinister and unexpected traitor in the midst and subsequent twist in the tail. (I'm disclosing no more than that or it will totally ruin the surprise element.)All I can say is BUY IT ! Another great from Anthony Strong.
OK, regarding the previous John Decker book ,I knew I'd be interested because the main subject base, Jack the Ripper, is a fascination of mine. Black Tide deals with WW2 and the German Navy; couldn't be more different, and so, I thought, this new book wouldn't be of such interest to me. BUT this book had me enthralled from start to finish. I read the whole thing in one sitting, loved the mix of past and present and the very sinister and unexpected traitor in the midst and subsequent twist in the tail. (I'm disclosing no more than that or it will totally ruin the surprise element.)All I can say is BUY IT ! Another great from Anthony Strong.
March 5, 2021
Another great addition to the John Decker series from Anthony M. Strong! This one is a bit different than what I expected but in a great way. It started off as a bit of a slow burn but that just gave time to really get to know the characters and for the atmosphere to build. Then the dread starts! What is going on in the scientific habitat deep in the ocean? What are the crew members seeing and experiencing? How is this German Submarine from World War 2 in pristine condition? Are there ghosts haunting the science team, or is it something else? Enter John Decker. It is cold and dark at the bottom of the sea and something wants its secrets kept. I volunteered to review a complimentary copy of this book but I truly recommend it!
April 1, 2021
A German Uboat, about 75 years old more or less, is found in the Atlantic, about 700 feet underwater, in remarkably good condition. CUSP has a project team on board studying the ship. When some "ghostly" things start to happen, John Decker is sent to the boat to try and figure things out. Additional events occur while he is there, including one of the team being murdered. One of the group isn't who they pretend to be, and then the whole teams' lives are in danger.
An interesting story. I thought the book started out very slow, and though I kept reading, I did not feel any real jolts until the book was about 80% done, which is why I rated it only three stars.
An interesting story. I thought the book started out very slow, and though I kept reading, I did not feel any real jolts until the book was about 80% done, which is why I rated it only three stars.
August 6, 2021
Another great John Decker thriller
This thriller takes place on the floor of the ocean where a pristine WWII German U-boat was discovered. Adam Hunt has sent Decker in to investigate some spooky stuff that has been happening to the researchers tasked with documenting the submarine. Although I figured out early on who the bad guy was, it didn't ruin anything of the story. Eventually it opened it up to so many more questions! The supernatural element in this book blew my mind! Anthony M Strong is getting better and better with each novel. He is becoming quite the master storyteller! Highly recommend
This thriller takes place on the floor of the ocean where a pristine WWII German U-boat was discovered. Adam Hunt has sent Decker in to investigate some spooky stuff that has been happening to the researchers tasked with documenting the submarine. Although I figured out early on who the bad guy was, it didn't ruin anything of the story. Eventually it opened it up to so many more questions! The supernatural element in this book blew my mind! Anthony M Strong is getting better and better with each novel. He is becoming quite the master storyteller! Highly recommend
November 3, 2021
I thoroughly enjoyed this entry in the series. There was plenty of mystery and excitement. The story was a bit of a departure from the usual monster hunt that I've come to expect and I liked the change. New characters who may or may not show up in future books were introduced. If you are a John Decker fan then you will enjoy this. It was a page turner and I will pick up the next book in the series soon. I'd do it immediately but I'm spreading them out because once I read the last one then I'll have to wait for the next book to be released and who wants to wait months for the excitement!
December 26, 2022
Another fun John Decker story. This was one of the better ones so far with Decker this time investigating a mysterious sunken U Boat that officially doesn't exist. It's a fun story with an interesting epilogue that seems to set things up for a long term story arc that will hopefully flesh this series out a little more.
These Decker books are grab and go stories. If you're looking for characters with depth and detailed back stories, you'll be disappointed. If you're looking for some quick and entertaining supernatural spookiness, this will work for you.
These Decker books are grab and go stories. If you're looking for characters with depth and detailed back stories, you'll be disappointed. If you're looking for some quick and entertaining supernatural spookiness, this will work for you.
September 28, 2021
Another great read
I chose this rating because it kept me interested and excited to keep going back to read more throughout the whole story. As usual i enjoy Strongs characters and creative supernatural twists. Decker is now at the bottom of the sea in a giant tin can sleeping amongst a killer. The strange happenings in the sub kept me guessing. I wonder if Thomas or the competing evil CUSP willl show up in another book in the series.
Very well done.
I chose this rating because it kept me interested and excited to keep going back to read more throughout the whole story. As usual i enjoy Strongs characters and creative supernatural twists. Decker is now at the bottom of the sea in a giant tin can sleeping amongst a killer. The strange happenings in the sub kept me guessing. I wonder if Thomas or the competing evil CUSP willl show up in another book in the series.
Very well done.
December 24, 2022
Black Tide was an outstanding supernatural icky bug. It was written in solid third-person, past-tense and the narrative was brisk and easy to read. The chapters and scenes were short and the grammar was excellent.
This is almost an historical thriller given the World War II U-boat, but most of it takes place in modern times. I liked the cast of characters, and the plot was cool. In the end, I had a great time and was able to close the book with a big smile on my face. Highly recommended.
This is almost an historical thriller given the World War II U-boat, but most of it takes place in modern times. I liked the cast of characters, and the plot was cool. In the end, I had a great time and was able to close the book with a big smile on my face. Highly recommended.
February 15, 2021
This is a brilliant read.
Wonderful well written plot and story line that had me engaged from the start.
Love the well fleshed out characters and found them believable.
Great suspense and action with wonderful world building.
Can't wait to read what the author brings out next.
Recommend reading.
I read a complimentary advance copy of the book; this is my voluntary and honest review.
Wonderful well written plot and story line that had me engaged from the start.
Love the well fleshed out characters and found them believable.
Great suspense and action with wonderful world building.
Can't wait to read what the author brings out next.
Recommend reading.
I read a complimentary advance copy of the book; this is my voluntary and honest review.
February 17, 2021
The Author Anthony Strong is at is again!
This book is for anyone who loves horror stories, action stories and stories that mix both! There are also historical elements which give an added sense of realism.
Please join our hero extraordinaire, John Decker, on another exciting ride. Don't miss it!
This book is for anyone who loves horror stories, action stories and stories that mix both! There are also historical elements which give an added sense of realism.
Please join our hero extraordinaire, John Decker, on another exciting ride. Don't miss it!
February 22, 2021
This was a great book. I was given an advanced copy in exchange for an honest review. I love John Decker and this one was amazing. History, mystery, adventure, and a nice little ghost story. Maybe or maybe not. You need to read the series and this one is by far the best. It does start a little slow but when the action starts it is non stop. Sit back and enjoy.
March 4, 2021
Another good book in an excellent series. This one was another one where my dislike for underwater misadventure had me wishing for dry land and a strong drink. The story was good, the characters interesting and the race to the end nail biting. I was especially happy with the ending. A delightful book to get hooked on.
April 4, 2021
After you start reading the John Decker series you realize you know him so well you can predict what he will do next. He’s like this old friend you look forward to reading letters from each month to see what is going on in his life. Another great read by Anthony Strong if you like a little hocus pocus mixed in with a fast action drama!
August 17, 2021
*Possible spoilers *
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As much as I love the John Decker series, and although we’ll written, it was definitely different in that it took place on a submarine and it wasn’t about hunting a monster. It was more a spy thriller. John didn’t have his usual crew of associates either. It was a good book, it just wasn’t my favorite of the series. I have read/reviewed Book 7 which was Awesome!
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As much as I love the John Decker series, and although we’ll written, it was definitely different in that it took place on a submarine and it wasn’t about hunting a monster. It was more a spy thriller. John didn’t have his usual crew of associates either. It was a good book, it just wasn’t my favorite of the series. I have read/reviewed Book 7 which was Awesome!
August 6, 2022
Still amazed!!
Another book in the John Decker series devoured! I can’t get enough of this series. John Decker has become one of my biggest heroes. His character defines strength, intelligence, & heart. With every adventure he never disappoints me. So glad that I began this series and once again I’m ready to travel with John for the next bizarre case.🤗
Another book in the John Decker series devoured! I can’t get enough of this series. John Decker has become one of my biggest heroes. His character defines strength, intelligence, & heart. With every adventure he never disappoints me. So glad that I began this series and once again I’m ready to travel with John for the next bizarre case.🤗
July 11, 2023
This book was really an interesting and surprising book as a submarine becomes trapped in something like a time vortex. What they think are ghosts are really Germans trapped in another dimension. Naturally, Decker catches on quickly on what is happening on the U-boat. I really enjoy the Decker series.
This entire review has been hidden because of spoilers.
August 14, 2025
I liked this book a lot. The history is interesting, the pacing is great and the characters and dialogue made sense. This is my first time reading this author and I really enjoyed the book. It’s a wild adventure and worth an afternoon to check it out. I need to read the other Decker books and catch up now
September 7, 2025
WW2 ghosts with a twist
Half of this book was very much around whether or not anything supernatural really was the answer of the mystery.
The other half was spent wondering who the bad guys really were.
A solid read, especially if you like a mix of sci-fi into your books.
It reminded me a little of Dean Koontz in style
Half of this book was very much around whether or not anything supernatural really was the answer of the mystery.
The other half was spent wondering who the bad guys really were.
A solid read, especially if you like a mix of sci-fi into your books.
It reminded me a little of Dean Koontz in style
Displaying 1 - 30 of 83 reviews