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Arko: The Dark Union

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A group of tweens unearth the most significant discovery in world history, designed to save the human species...from itself.

Ariel Hyden and his friends accompany their parents, some of the world’s top scientists, on a trip to the Yucatán where Dr. Hyden is conducting research for the Mexican government. On the kids’ exploration of nearby old Mayan grounds, they discover an impossibly advanced structure hidden for millions of years in the bowels of the earth that is responsible for the past—and future—of the world as we know it.

A perilous mission has the children and the scientists racing to find answers to the purpose of their incredible discovery and who created it. With federal officers, armed soldiers, and nefarious individuals in hot pursuit, the group must be successful—the fate of the world is counting on them.

With thought-transmitting abilities, an ancient entity buried for millions of years, hatching flying pterosaurs, and futuristic technology, ARKO: The Dark Union is a thought-provoking and realistic story steeped in scientific facts, speculating on humanity’s ecological destruction and its survival.

292 pages, Kindle Edition

Published January 15, 2022

28 people are currently reading
676 people want to read

About the author

U.W. Leo

4 books10 followers
Young adult author U.W. Leo was inspired as a young child to become a writer, having spent much of his childhood with his uncle, David Shachar, a well-known Isaeli writer and winner of the prestigious Prix Médicis award, a French literary award for fiction writing. The seed for Leo’s writing passion was planted and grew as he continued writing short stories, poems, and letters. U.W. Leo's first novel, Red Silkworms, won the Emerging Authors award.

An interesting experience that U.W. Leo has while writing is the feeling that the book is writing itself as the story comes to life on its own, seemingly with no control from U.W. Leo, and that the story is also writing a part of his own existence. He finds this process to be magnificent and a reflection of the wonder of life itself. In recent years, Leo is dedicated to writing his Sci-Fi Series: ARKO.

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Displaying 1 - 21 of 21 reviews
Profile Image for The Bookish Elf.
2,888 reviews451 followers
August 16, 2022
"ARKO: The Dark Union by U.W. Leo" is a fascinating new beginning to a series about a band of tweens who are on a mission to save the human race and uncover the most significant discovery in the history of mankind. This tale is an amalgamation of the helplessness and innocent ignorance of childhood with the age-old wisdom of the universe, of wonder and mystery, and the inexplicable and unfathomable abilities, as well as things that lurk around the corners of reality and seep through the cracks in the world.

The narrative focuses on Ariel Hyden and his companions as they go to the Yucatán with their parents, who are considered to be among the most accomplished researchers in the world. Dr. Hyden, Ariel's father, is now working as a researcher for the Mexican government. When the kids go on an adventure to some nearby ancient Mayan ruins, they find a "flying saucer," a structure that is an unbelievable technological marvel. It has been dormant for millions of years in the earth's core and is ultimately responsible for the history and destiny of our globe.

The youngsters and scientists are on a dangerous journey to understand the origins and ultimate purpose of their astounding finding as quickly as possible. Even though they are being pursued by armed troops, federal agents, and other shady characters, the group must be successful since the future of the world depends on them. This narrative is both thought-provoking and realistic, based on scientific facts, and speculates about the devastation of the environment and the possibility of its survival, using elements such as thought-transmitting abilities, an ancient structure buried for millions of years, the hatching of flying pterosaurs, and futuristic technology.

The story of "ARKO: The Dark Union" is presented with an exceptional understanding of all that makes us human. It demonstrates the power of storytelling to both illuminate and protect us from the dangers that lurk inside and around us. It is a thrilling, shocking, and adventurous fable that is as delicate as the wing of a butterfly and as dangerous as a dagger in the dark. The book delves into alien technologies and ancient mysteries, touching on themes that echo between our mature selves and our inner child.

U.W. Leo is a skilled storyteller who successfully immerses the reader in the action. While reading, we feel as if the author is sitting right next to us, sharing his experiences. He takes us by the hand and introduces us to a dark, tangled corner of the universe full of things that make us shiver and hold our breath in the dark. "ARKO: The Dark Union" is genuine and captivating, and it conceals a great deal beneath its intriguing surface. The tale creeps into us and lingers, much like a secret whispered in the shadows by a trusted friend. The author captures the elements of childhood so beautifully, evoking many emotions of wonder and excitement.
Profile Image for Linn J.
962 reviews20 followers
October 10, 2023
DNF okay I was optimistic when I started to read but now it feels that I'm stuck in quicksand. It's slow and if you do like Star Wars I can maybe see that you would like this book, unfortunately I don't like Star wars so this was not my cup of tea.

The character were hilarious though so if it wasn't an arc with time limit I would maybe, just maybe try to read through but it didn't pick my interest enough... I'm sorry
Profile Image for Lourdes.
566 reviews7 followers
March 28, 2022
Thanks to BookSirens for this ARC!

I really enjoyed it, like history!!

"A perilous mission has the children and the scientists racing to find answers to the purpose of their incredible discovery and who created it. With federal officers, armed soldiers, and nefarious individuals in hot pursuit, the group must be successful—the fate of the world is counting on them."

I would definitely recommend it to young children, and even adults. I like Sci-fi, and this was really good.

(I finished a long time ago, just behind on my reviews!)
Profile Image for Giora.
80 reviews1 follower
January 27, 2022
A breezy read with some good messaging.
Great for teens who love adventure and intrigue.

I read this book for free during its original release window.
Profile Image for AR.
489 reviews15 followers
did-not-finish
March 16, 2022
Well…I tried! But this simply isn’t something I want to continue reading for whatever reason. Will leave unrated because I only got half a chapter in.

Thank you to NetGalley for the arc.
Profile Image for Michelle (Chelle's Book Ramblings).
292 reviews4 followers
May 30, 2022
The first thing I’m going to say about Arko: The Dark Union is that it is a good book. It’s not amazing; it’s not even very good, it’s just good. 

If you ask me if I would recommend it, my answer would be yes. As a matter of fact, that’s what I’m doing right now! But let me warn you: the book has issues, and a lot of flaws.

One flaw that stood out to me, personally, is its lack of identity. on the author’s website the description reads “A group of tweens unearth the most significant discovery in world history, designed to save the human species...from itself”.

 A couple of chapters in and I was thinking “this book isn’t middle grade”. Those tweens do not behave like 12-year-old kids; they behave like twenty-something young adults. Their parents, legal tutors or whatever, treated them as equals instead of children in their care.

That’s another issue; bad parenting. The parents or legal tutors of these children, all scientists, by the way, are the worst parents in the world AND the worst scientists in the world as well. 

In the book, the kids find some pterosaurs’ eggs and the parents’ great idea was to change their genetic code, (waaaaay unethical, by the way), and give a freaking flying carnivorous dinosaur from the Triassic period to the kids for them to raise them! (For those who have seen Jurassic World, those things that eat the nanny? That’s what I’m talking about)

 I was still thinking “cool, something like How to train your dragon or whatever” until I found a pterosaur image… That’s just silly.

In a nutshell, the people that are in charge of the welfare of children let them ride the carnivorous gigantic lizard through the sky, like Link did in the Skyward Sword video game. 

But they are not only bad parents, as I mentioned before; they are bad scientists as well. They talk scientific gibberish, jump to baseless conclusions and touch everything that they find without proper protocol. Sometimes I wondered if I wasn’t reading the script from the movie Prometheus.

I apologize in advance because we are getting into Spoiler Territory, so be warned and read at your own risk..

The book has lots of contradictions and lots of unnecessary things. And I don’t blame the author for this, I blame the editor who didn’t tell him how this part contradicts this other part, or that capturing a bunch of kids and not locking the door is stupid; and mostly how 12 year-olds with guns is a big NO in storytelling, especially if it adds nothing to the plot.

Then there’s this thing in the end… that takes away the entire Character agency from the story. So yeah, that… thing… justifies all the contradictions that I mentioned above.

If you ask me: aren’t all those things enough to skip this book? It would depend on your ability to turn off your brain and just enjoy the ride.

 Regardless, the book has good characters, you really care for them; it has a good story, even if a bit  convoluted, that involves Aztec mythology mixed with ancient technology, alien civilizations and, of course, we can’t forget the dinosaurs. But more importantly, this is the first book of a series, so there is a chance for improvement.

Reading Arko: The Dark Union is like watching a B movie or an OK tv show. It is not the Godfather or Star Wars (the old ones) of books; more like Fast and Furious Tokyo Drift or Return of the living dead 2.

 You’ll be entertained and have a good time with it. Afterwards, you can discuss bad parenting with your friends who have read it, in reddit or Disscord.
Profile Image for Sondang Panjaitan.
28 reviews
November 2, 2023
"ARKO" by U.W. Leo is an enthralling sci-fi adventure that explores the convergence of humanity, consciousness, and the urgent need to address environmental issues. Leo's storytelling captivates readers from the very beginning, and his narrative is an engaging blend of exhilarating action, profound insights, and well-crafted characters.

The story kicks off with a mysterious message transmitted globally, demanding an end to all wars and a shift towards using the energy of the stars. This proclamation echoes in government centers worldwide, causing chaos and panic. As world leaders grapple with this enigmatic voice, a missile carrying nuclear warheads takes an inexplicable course, setting the stage for a riveting and unpredictable journey.

Leo's characters are multi-dimensional and relatable. From President Don Browning to the inquisitive group of children led by Ben, each character undergoes significant development. Their development and interactions as the tale progresses are crucial to the plot's success. The kids in particular give the story a new perspective and inspire optimism for the future.

The narrative of the novel combines adventure, ecology, and science fiction. Leo skillfully blends these components to create a plot that makes readers think about important global concerns while keeping them on the edge of their seats. The environmental message, in particular, serves as a powerful and timely warning of the environmental effects of human activities. It is a call to action, encouraging readers to take responsibility for the environment.

The pacing in "ARKO" is well executed. Leo makes sure that the plot never seems hurried or slow by striking a balance between dramatic action sequences and reflective pauses. Readers are drawn into the world of the novel by the author's detailed descriptions of locations and events, which demonstrate his attention to detail.

The author's writing style is engaging and polished. The absence of typos and grammatical mistakes in "ARKO" improves the reading experience. Leo's impressive ability to make complicated topics clear makes the book accessible to a wide readership.

The work clearly demonstrates U.W. Leo's background in environmental science and policy. For those who are interested in the nexus of science, politics, and fiction, his knowledge lends legitimacy to the environmental problems the story explores.

In summary, U.W. Leo's "ARKO" is an action-packed, thought-provoking science fiction adventure that succeeds on several levels. The well-developed characters, engaging plot, and environmental message create a memorable reading experience. Leo's work demonstrates his proficiency with narrative and his knowledge of his surroundings. Anyone who likes science fiction experiences with a deeper message should definitely read this book. "ARKO" is deserving of a strong five-star rating since it gives readers a lot to think about regarding the future of our planet and our place in it.
2 reviews
December 19, 2023
Arko: The Dark Union by U.W. Leo is a book for children and tweens that combines adventure, advanced technology, and ancient creatures. The story is about five twelve-year-olds from varying cultures who are brought to the Yucatán Peninsula by their parents, a team of renowned scientists performing research work. The children were given free rein to explore, and during one of their adventures, they stumbled upon a mysterious cave and found a highly advanced structure that is billions of years old and has the power to alter the entire world.

The book is good—not too bad or too good. Throughout the novel, I liked how the characters gave different perspectives and hypotheses about their environment, discovered structures, or what’s happening. I can see that it reflects their culture and personality, whether they are logical or more imaginative. The characters had a lot of dialogue; some were good, and some felt a bit flat or unnecessary. Also, as the book progresses to the end, the five children, especially Ben, sound and think more like adults and even wiser.

Moreover, some scenes are beautiful, and the ending gave me an eerie feeling. It sounds like an apocalypse or invasion is coming to the whole world, and many things will change. As Ben said, they will create a new cosmic order. But I have a question: will the environment and its creatures benefit from this new order, but will humans suffer as a result?

Although this book has its strengths and has an interesting idea behind it, I find the writing lacking in descriptive words. It doesn’t show me the scenes. 90 percent of the time, the story is told. The characterization is a bit flat, so I don’t feel much connection to them. And honestly, when the characters are talking about scientific ideas and mentioning scientific terms, it feels like reading a dictionary definition. Therefore, I give this a rating of three out of five stars.
Profile Image for Valerie Campos.
3 reviews1 follower
November 10, 2024
Arko: The Dark Union is a thrilling and intricately woven sci-fi adventure that plunges readers into a gripping, fast-paced universe filled with high-stakes conflict, complex characters, and a sense of urgency that keeps you hooked from start to finish. The story centers around Arko, a skilled and resourceful protagonist, who is drawn into a dark and tumultuous conflict between warring factions in a galaxy on the brink of collapse. The book excels in its world-building, with each planet and species richly detailed, creating an immersive experience that feels both expansive and alive. The author skillfully combines elements of space opera with political intrigue and intergalactic warfare, all while exploring themes of power, loyalty, and personal sacrifice. The balance between action-packed sequences and deep character development ensures that readers are not only invested in the fate of the universe but also in the characters who inhabit it.

However, while the story offers plenty of excitement and intrigue, there are moments when the pacing falters, particularly during lengthy expositions or when the narrative slows down to delve into political maneuvering and backstory. Some readers might find these sections a bit drawn-out, especially when compared to the otherwise fast pace of the book’s action scenes. Additionally, while the characters are compelling, certain secondary characters feel underdeveloped, leaving some subplots feeling incomplete or rushed. Despite these minor flaws, Arko: The Dark Union delivers a solid and engaging sci-fi experience, with plenty of twists and turns to keep readers coming back for more. Overall, it’s an enjoyable read for fans of the genre, offering a mix of adventure, action, and moral complexity that sets the stage for what promises to be an exciting series.






Profile Image for Tabitha  Tomala.
889 reviews119 followers
July 5, 2022
This review is also featured on Behind the Pages: Arko The Dark Union

Thank you to U.W. Leo for providing me with a copy of this book! I voluntarily leave this review!

Arko: The Dark Union is an ambitious book. There are many characters introduced to the reader, described by their race and physical features. And while there was a multicultural cast of characters, the presentation did not quite come off appropriately. There were moments where the characters internal and external dialogue described other races and cultures in clipped tones, edging towards insult instead of a proper introduction. The diverse cast was well intended, but a softer approach to introducing the characters was needed.

That being said, the characters did work well together. Each had their part to play as they made discoveries and began to experiment with the remnants of a lost civilization. And while there are high-tension moments, the characters promote an overall environment of collaboration.

It was a bit difficult to keep all the characters in mind. The writing lived in the moment through telling rather than showing, and the characters did not stand out enough from one another. There were also moments where certain characters would make questionable choices, and rather than contest the plan, the other characters simply agreed even though they held reservations. If there had been a stand between different characters, their personalities and morals would have helped to make them stand apart from one another.

But I did enjoy the science and advanced technology brought into the story. It was fascinating seeing the advancements made and the discovery of what could be done by combining the science of today with the science of the past. And while sometimes the sciences were beyond my understanding, the context they were placed in made them easier to digest.

Arko: The Dark Union is a sci-fi adventure filled with science and dinosaurs. The writing style is fast-paced and plot-driven, focusing on the ever increasing discoveries of the characters. This novel would be best suited for teenagers as some of the ideas and language used may not be suitable for younger readers.
Profile Image for Lori Alden Holuta.
Author 19 books68 followers
March 16, 2022
While scientists in Mexico work on Mayan ruins research , their offspring are off discovering—and playing around with—ancient alien technology. Eventually they do the right thing and bring their parents in on the discovery. As the grownups and kids explore deeper, they find dinosaur eggs...and figure out how to hatch them! That's when the fun really starts.

My only reservation is that the characters seem as if they aren't fully developed. Their emotions tend to be simplistic, or absent. Possibly this has been amplified by the process of translating the book into English. I may be overly picky about that, and I wouldn't let it deter you from giving the story a chance.

Overall, this is a cute, engaging, message-driven book that should keep your tween reader engrossed to the end.
Profile Image for Delphia  Von Heeder .
1,744 reviews53 followers
January 17, 2022
Well is Book 1 in The Dark Union by U W Leo. I felt that this book was a story on pollution and ecology. It is a WiFi and I thought this book was interesting. It is set during contemporary times. The children of scientists discovered A flying saucer in the Mayan ruins. Everyone all over the world wants the ship. Governments want to destroy it. The aliens want humanity to change and clean up the world. Who wins? Book 2 is coming! I received an arc for free and am leaving my review voluntarily.
1,978 reviews72 followers
March 9, 2022
I'm always looking for books to encourage young readers and this is one I would recommend for the one interested in sci-fi with an lively imagination. It has these five young engaging kids along with some ancient pterosaurs, lots and lots of action and suspense along with some current real world issues to deal with. I think there's lots here to keep them reading and to get them thinking.
I won a copy of this book in a Goodreads giveaway for this honest review.
Profile Image for Alicia Marsland.
Author 7 books9 followers
April 30, 2022
Hopeful story

I could argue with a lot of it but it’s basically for early teens so not really intended to be taken seriously except for the problems that the story highlights. Not for Christians really, as Christians have different hopes and believe in different solutions. But anybody can enjoy a good story.
Profile Image for Becky Fields.
131 reviews
June 22, 2022
I enjoyed this book. It’s a great mix of science and overall problems the world is currently facing. It is a quick read that keeps you guessing. It left me wanting to know what happens next. I am interested in seeing how they resolve the conflicts, global warming, and bringing all cultures together in the future continuations.
Profile Image for Ray.
7 reviews
July 31, 2022
A big thank you to U.W Leo for providing me with an ARC for his great book!
This was such a fun read and I definitely recommend to all fans of fantasy and science! It’s also a perfect read for middle-grade and young adult fans of any age.
It’s so easy to be fully immersed in this book and envision every moment of disaster, difficulty, fun and triumph!
Profile Image for Sarah Berry.
5 reviews
November 9, 2024
This was a mixed experience for me. There were parts that I loved, but there were also sections that felt like filler. The writing was good, but the story was a bit too predictable. It’s not a bad book, but it didn’t quite live up to the hype. Worth a read, but manage your expectations.






Profile Image for Casarah Nance.
233 reviews2 followers
January 28, 2023
I can tell the author put a lot of thought in this book, there was a lot going on and a lot of characters in the mix. I struggled to read it and enjoy it but the concept was interesting.
Profile Image for Ceren K..
3 reviews
March 4, 2023
Scenes feel rushed
Too many characters introduced too fast
The world building feels... not so built
Profile Image for Susi.
43 reviews5 followers
December 2, 2023
The author's love for Mexican culture, people, and authorities inspires me to dedicate him the song "Frijolero" by Molotov.
Profile Image for Susan Atherly.
406 reviews87 followers
March 29, 2023
Spoiler free. Arko has great characters and a good, fast paced story. It does, however, suffer from "new writers' syndrome" where the actual writing is awkward in places and there is a bit of over explaining. The story is worth sticking with it and I look forward to the next book!
Displaying 1 - 21 of 21 reviews

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