The Forbidden River

Dash Boone Thrillers #2

by Craig A. Hart, Nick Thacker

They wanted a super soldier. They created a monster.

Deep in the heart of the Amazon, a covert facility is churning out something inhuman.

Dash Boone and Kim Kirby were lured to South America chasing a myth—a rumor of a man creating super soldiers. What he found was exactly a nightmare.

Verstärkte—genetically enhanced soldiers, faster, stronger, and utterly unkillable.

As the jungle closes in and the body count rises, Dash and Kim must rely on their wits, skills, and perhaps even a bit of luck to survive.

The only way to stop what’s coming… is from the inside.

Perfect for fans of James Rollins, Matthew Reilly, and Michael Crichton, The Forbidden Isle is the electrifying second book in the Dash Boone Thrillers, a pulse-pounding action thriller packed with breakneck pacing, high-concept science, and the kind of edge-of-your-seat suspense that’ll leave you breathless.

356 pages, Kindle Edition

Published November 4, 2025

About the author

Craig A. Hart is a writer of thrillers. In a past life, he was also director for Northern Illinois Radio Information Service, a broadcast outreach that brought daily news and information to the visually impaired.

In 2015, Kindle Press published his literary novel BECOMING MOON. NPR affiliate Northern Public Radio featured BECOMING MOON in their Winter Book Series, and it won Best Novel of Summer 2015 from Pinnacle Awards. He is also the author of the historical mystery NIGHT AT KEY WEST, which is based on true events.

In 2016, he publishing SERENITY, the first book in the popular Shelby Alexander Thriller Series. Serenity alone has been downloaded over 400,000 times by eager readers.

In 2022, he launched the Maxwell Barnes Adventure Thriller Series, co-written with S.J. Varengo. The award-winning first book in that series, MAYAN SHADOWS, was published on May 11, 2022. Two more books follow in that series: MAYAN THUNDER and MAYAN TEMPEST.

A native of Grand Rapids, Michigan, Craig lives in Iowa City, Iowa with his wife, sons, insane dog, and anti-social cat.

Reviews

[David Eve · Rating 5 out of 5]

Nazis and an absence of pain in the Amazon!

80 years ago, fleeing Germany, Vogler throws Kessler to the Allies to aid his escape. Fast forward to now and their descendants have a score to settle...
Dash first meets Kessler when the old man he met while fishing, is gruesomely murdered, after trying to reach Dr. Kirby. Kessler sets them on Vogler's trail after infecting Dash with a defective prototype of the drug that Vogler is developing to eradicate pain to create super soldiers to take over the world....
The trail leads them into the Amazon...
Chock full of gruesome descriptions, action, suspense, intrigue and an undercurrent of romance and revenge make for an entertaining tale as Vogler's atrocities become clear.

[Manie · Rating 4 out of 5]

I guess any dictator would love to have a company of soldiers all resembling "The Hulk". That company would be unconquerable.
Except in The Forbidden River an ex Nazi's son had a dream to exactly that. In a hidden enclave in the Amazon, that is exactly where Vogler did everything in a secret laboratory to create such an army of unbeatable soldiers.
Except these soldiers are without any feeling at all.
And this is when Dash Boone got involved. And Kim Kirby.
And annihilation becomes a very possible reality.
The joint talents of Nick Thacker and Craig Hart certainly created a heart pounding thriller in The Forbidden River.
Enjoy.

[Stephanie · Rating 5 out of 5]

A breath of fresh air! Well not all the time, if you take into account what happens almost at the end, but I'm not giving anything up, you need to read it to understand.

I liked that the hero in this novel can be whoever you want it to be because it's not made 100% clear who you are expected to see as that character.

I also loved the direct references to Recent History, I'm just a bit of a history geek.

I'm looking forward tho the next instalment...

[ukkindlecustomer · Rating 5 out of 5]

Man and Superman

Nazi experiments, practical examples of how moral and ethical debate sometimes needs a quick decision, in almost Nietzchean adventure thriller set in the Amazon rainforest. Humerous dialogue from likeable pair in second "Forbidden" book.

[Jackie · Rating 5 out of 5]

Wow what a story, full of surprises and suspense What will Dash and Kim find deep in the Amazon. Theres danger lurking everywhere, how will things turn out Impossible to stop reading until the very end. Can’t wait for the next book to come out.

[Phthon · Rating 5 out of 5]

Well that was terrifying! The whole concept of the Verstärkte goes against nature and human decency. However they were truly victims as well. But the most terrifying part is that this probably holds a grain of truth. I loved reading this book! It was FANTASTIC!

[Susan · Rating 4 out of 5]

Action packed, with intriguing characters, this tense, edge of your seat story will definitely keep your attention.

[Texas · Rating 4 out of 5]

THE FORBIDDEN RIVER, #2 - An interesting story c combining humor, action, serums, and monster Nazi soldiers. Good characters and interesting story lines set to a good pace. Source: The authors. 4*