Shadow of the Eternal Watcher

by Josh Mendoza

Duster Raines has demons. Some visit him in his dreams, reminding him of the choices he made in combat to survive. Others visit him while he’s awake, demanding he pay penance for those sins. But lately, he’s started seeing an alternate version of reality where he leads a life of importance full of wealth and power. Visions so vivid, they seem more real than the life he lives as a PI, scrounging the gutters of Los Angeles for an easy buck. It’s enough to drive anyone insane. Pulled into a missing persons case he never wanted, Raines finds himself framed and hunted by the government. But as he searches for answers to clear his name, he discovers a truth he never could have imagined. He possesses the ability to bend spacetime to accomplish incredible feats. With these powers, maybe he’s got a shot at the life he deserves. There’s only one problem standing in his way, the other Duster Raines.

Genres: Science Fiction, Fantasy, Thriller, Fiction, Action, Mystery

325 pages, Paperback

Published January 28, 2025

About the author

Josh Mendoza is an award-winning filmmaker known for his post-apocalyptic feature film, What Still Remains, and his genre-bending debut novel, Shadow of the Eternal Watcher. He received a BA in English and Creative Writing from Stanford University and earned an MFA in Film and Television Production from USC’s School of Cinematic Arts. He has since split his time between the City of Angels and the deserts of Arizona with his wife and two children.

Reviews

[Emma Kelly · Rating 4 out of 5]

3.75⭐️ Shadow of the Eternal Watcher by Josh Mendoza is a fusion of noir mystery and sci-fi all wrapped up in a blockbuster format.

As a single, broke, alcoholic with PTSD, private detective Duster Raines hasn’t got a lot going for him.
In desperate need of cash, he agrees to meet Madison Andrews to investigate the disappearance of her husband, Dr. Andrews.
Little does he know that this case will plunge him into unknown depths. He uncovers secret tunnels, a green stone that casts weird shadows of himself and robot dogs; all whilst eluding a group of elite mercenaries who are tailing him.

We can definitely see Mendoza’s background in screenwriting shine through in this novel as the action sequences are as if plucked right out of a film. Raines’ inner struggles mixed with a high stakes plot really strike a great balance between psychological depth and action.

The cast of characters is great, the plot is well thought out and leaves us wanting more at the end; perhaps a sequel is on the cards?

I was really hooked until the end and could definitely see this as a movie.

Fans of noir mysteries with a supernatural edge will eat this up.

Thanks to Josh Mendoza, Inkshares and NetGalley for the ARC of this book in exchange for an honest review.

[Joe M · Rating 5 out of 5]

Shadow of the Eternal Watcher is a masterclass—quietly unsettling, beautifully written, and full of reveals that reward close reading. Mendoza blends intimate character work with big, imaginative stakes, so every twist lands with emotional weight. If you’re looking for a fresh take on detective noir with dark science fiction elements, this is a must‑read.

[Marie Parsey · Rating 5 out of 5]

Just a great combination of science fiction and a noir style detective story. The story pulled me along so that I did not want to put it down. The character development most especially, of Duster Raines was intriguing. And most definitely would love to see a sequel.

[Peter G. · Rating 5 out of 5]

Well-structured, fast-paced, and a lot of fun!

[Jen · Rating 4 out of 5]

Thanks to NetGalley for the eARC

Well written and evenly paced tale of an almost stereotypical hard-boiled detective who discovers he has the ability to access alternate universes, via his 'Shade' (a quasi clone of himself), who has ambitions of ruling the Universe (of course). The story benefits from a first person narration, and would fit well in the MCU. Hopefully this is the first of a series, as the novel ends after a climatic battle, and with the potential for more.

[Karen Kumar · Rating 5 out of 5]

Loved this book, a fantastic and riveting combination of sci-fi and detective noir. As I read, it was like a movie playing in my head. The protagonist is a detective with a complex background that includes combat veteran, alcoholic and former cop. He's smart, determined and gritty with a dry sense of humor. There's plenty of action in the story and the sci-fi part is truly fantastical. It's a page-turner and very enjoyable read. I highly recommend!

[Janice · Rating 5 out of 5]

Sci-fi thriller is not my normal genre, but throw in a detective story and I become intrigued.

I thoroughly enjoyed this book. I'm hoping for a sequel.

[Jillian · Rating 3 out of 5]

Sci-fi 🪐 Thriller. Duster Raines, a disgraced cop turned P.I., with a drinking problem is haunted by a boy he killed during his military tour. Hired by Madison Andrew to find her husband who she claims has been “abducted by aliens” 👽, Duster finds himself on the run after being entrusted with a stone ring. Through his dreams he is connected to his “shadow” aka his double in another universe. Of course, his shadow is a powerful leader looking to take over earth and sustain his people! No one is to be trusted-including himself. Final thoughts: I had no clue what I was getting into when I started this book and was surprised how on the edge of my seat I was as each chapter progressed. Duster is oddly a likable character—someone who has been dealt the short end of the stick, in some regards and others— well he put himself in sticky situations. Lots of twists and turns along the way aka robot dogs and stone tails. Overall an interesting read! #shadowoftheeternalwatcher #joshmendoza #goodreadsgiveaway #goodreads #sciencefiction #thriller #book #bookreviewer #bookreader #jillianhereforthebooks

[Stephen Parsey · Rating 5 out of 5]

Shadow of the Eternal Watcher grabs you from the first page and doesn’t let go.

In his fantastic debut novel, Josh Mendoza fuses old school detective work with pulse-pounding action and sets it all against the backdrop of a society that is tearing itself apart at the seams - even though it doesn't appear so on the surface.

The story pulses with a kind of visual energy that makes it easy to imagine as a moody motion picture in your mind. My favorite aspect of SotEW is how Mendoza unveils his dystopian setting gradually, mirroring the descent of his main character, Duster Raines, into entropic chaos. Watching the world disintegrate through Duster’s increasingly fragmented perspective keeps the reader guessing about what's around every corner.

For fans of cross-genre storytelling, Shadow of the Eternal Watcher is a must-read. It manages to be both intelligent and adrenaline-fueled—an ambitious, layered narrative that heralds the arrival of an exciting new voice in fiction (and sci-fi in particular!). I can’t wait to see what Mendoza does next, and here’s hoping someone in Hollywood is already working on the adaptation of Shadow of the Eternal Watcher.

[Mark Owen · Rating 4 out of 5]

This is a well executed detective noir SciFi. After LA private investigator Duster Raines is hired to find a husband taken by aliens, he takes the job because the woman is beautiful and he needs the money. There’s more to the story that confuses him, and he starts having strange dreams of other worlds. It eventually leads him to a parallel universe with superior technology that plans to invade ours. It’s a great read, but a few of the secondary characters I found it hard to understand their motives.

[Monique · Rating 5 out of 5]

this book (!!!!) is a fast-paced, action, sci-fi, noir-esque, mystery adventure!! the MC is complex and intriguing, the plot contains many elements that reveal a layered story and unexpected twists that made this such an enjoyable experience!! i love the writing, the characters, and the ease with which i could see everything happening (i’m reiterating the incredible writing) even though there was, at times, a lot going on…i hope there will be a sequel! 🤩💞✨

[Jake Smolowe · Rating 5 out of 5]

Excellent blend of space opera and noir-style detective story, with thrilling action scenes, and plenty of dry humor. The main character is complex & tragic, but ultimately likable, always trying to do the right thing when push comes to shove. Highly recommended, can’t wait for more!

[Vicky Locke · Rating 4 out of 5]

Really dug this! Duster is a well fleshed-out main character that I enjoyed spending time with. It had a nice balance of action, humor and heart. I listened to the audiobook and the narrator was fantastic. Hoping for a sequel!

[Pablo · Rating 5 out of 5]

The most fun read I’ve had in a long time. SotEW is an incredibly creative and well-spun yarn that keeps getting more exciting with every chapter. Highly recommend for fans of sci fi adventure.

[Susan · Rating 5 out of 5]

I just went from a cozy mystery to reading this sci-fi. I won this book, so had to give it a try. Very intriguing situations.
Captured my attention to the very end.
Well written.

[Shane · Rating 4 out of 5]

This was well paced and well written with compelling characters and an engaging story. Sci-fi noir thriller with a little fantasy element. A nice surprise (Hoopla bonus borrow). 4 stars.

[Matt · Rating 5 out of 5]

This is the only book I have read twice this year. It is well written and worth a read. I really enjoyed the story and the characters as you get to know them.

[Lou Ronayne · Rating 5 out of 5]

What a thriller. Josh did an excellent job of developing the characters. It was suspenseful and unpredictable. I highly recommend this book.

[R Cast · Rating 5 out of 5]

Shadow of the Eternal Watcher is a great mystery. It was nonstop action from start to finish and I couldn’t put it down. I loved the book. I'm looking forward to more from this talented writer.

[Brittnay · Rating 4 out of 5]

I won this book from a giveaway hosted here on Goodreads! So, shout out to Inkshares for hosting that giveaway and picking me!

Also, I wanted to post this review sooner, but life happened.

I will say that sci-fi thrillers are not usually something that I read commonly. So, winning this and reading it was a nice change of pace! I loved the characters and all of the dry humor in this book! It was very entertaining overall! I'm excited to see the future works for this author!

[Jesse Roberts · Rating 5 out of 5]

This book was a lot of fun!

Noir detective that blends into epic sci-fi fantasy. Funny, action-packed, and unique. I call that the Big Three when I'm looking for a new book.

Definitely looking forward to the next book.

[Alison Faichney · Rating 4 out of 5]

Nice little sci fi action thriller. Mendoza is a completely new to me author and I can’t even remember what drew me towards this book. Likely the cover or description but either way, this was great introduction to Mendoza.

The story is a bit complicated but mostly follows Duster Raines, former soldier/LEO officer who now spends his days as drunk as tolerable while picking up work as a private investigator. Things get pretty wonky fast and this book veers from a standard crime thriller into something much more complicated. We have parallel universes, competing timelines and some wild aliens.

The characters were solid although Raines felt a bit cliche in his detective role. His random bond with Juan was a bit sudden but I still enjoyed Raines, Juan and Carla. Around the halfway point the book starts exploring these themes of multiverses and wormholes and the plot fractures somewhat. Between the various characters we meet, their shades and these competing factions for control of reality things get a bit murky. There’s a few characters who I’m still not sure are benevolent or not. This definitely feels like Mendoza is setting the stage for further books in this series.

Also around the halfway point the book veers into more cinematic territory as well. Some of the dialogue and action scenes felt a bit cliched and convenient toward the last third of the story.

Overall I still really enjoyed the read. I’d absolutely be willing to check out a sequel (if written) as multiverse and sci fi thrillers are definitely in my wheelhouse. This is a pretty solid example of both and I look forward to seeing what Medoza puts out in the future.

[Margaret Bowerman · Rating 5 out of 5]

Prepare yourself for an electrifying adventure with Josh Mendoza’s ‘Shadow of the Eternal Watcher.’ When Raines, a drunken and broke PI, becomes entangled with a relentless shadow personality and foes from an alternate universe, the scene is set for a gripping narrative of peril and intrigue.

With so much at stake, new alliances come together to battle forces that could mean the very end of Earth. Richly drawn characters and mesmeric action make this a story that will stay with you long after reading this thriller.

[Phoenix Heat · Rating 5 out of 5]

Detective thriller for the ages. It constantly kept me intrigued. I couldn't put it down. I read it and then I listened to it as well.

[Pallavi Sareen · Rating 4 out of 5]

Shadow of the Eternal Watcher by Josh Mendoza achieves the remarkable feat of blending two very different genres of fiction: detective crime noir on one hand and alien fiction on the other. In my opinion, if it weren’t for the prologue, the metamorphosis the story undergoes near the middle of the book would have been all the more incredible.

Duster Raines, at the beginning, is the typical detective you would expect to find in crime fiction. He has demons from the past to deal with, a pretty female client giving every hint of being a femme fatale, and a few FBI agents strangely interested in him. And of course, he is soon on the run. The robo-dogs were, however, an interesting turn. The case is of a missing person, but there may be aliens involved. Since the reader has already read the prologue, they believe aliens are probably real but I personally believe the suspense would have been greater without it. The prologue does, however, pave a smoother path into the alien fiction elements.

The plot is the biggest highlight of this book, successfully marrying two genres that are rarely coupled together, while keeping readers on their toes through a long series of twists and turns.

Another strength of the book is the concept of the Shade which was remarkably well done. A Shade is a creature in another universe that's a duplicate of you. Raines has a Shade, and it is the very worst villain of the other world: a dictator.

The way these people from different worlds come to learn of and discover each other is equally remarkable. It is first achieved through strange nightmares experienced by some. I don’t wish to give away more details, but there is a lot more to this. All I will say is that Raines starts with a case he didn’t want to take, then ends up on the run from justice for a crime he didn’t commit, and ultimately finds himself fighting a battle that isn’t even of his own world.

All this contributes to some incredible world-building, and it does, but I personally found the prose uninspiring. Though the pace of the storytelling mostly makes up for it during the detective fiction segments, it was more problematic for me during the extraterrestrial sections.

The characters also seemed to lack any distinctive traits beyond their detective world stereotypes. Once again, the pace of the book could excuse some of it but not entirely. Most of them are missing any kind of memorable personality.

Despite all these limitations, the book kept me interested throughout with its twists and turns—and that, I think, is its key selling point. Its cinematic experience keeps it entertaining.

Overall, I think Shadow of the Eternal Watcher is an excellent page-turner that, despite its weaknesses, should intrigue readers of both crime noir and alien fiction. It is definitely recommended for fans of either genre and I would certainly be interested in its sequels.

[Sidharth Vardhan · Rating 4 out of 5]

“Shadow of the Eternal Watcher” by Josh Mendoza reminded me—low key—of The New York Trilogy by Paul Auster, in that the stories are ostensibly detective fiction but turn out to be something else entirely.

Duster Raines is a detective haunted by demons from the past, among other things. Then he starts experiencing what seem to be hallucinations. The story properly begins when he meets a woman who has “femme fatale” written all over her and takes a case from her:

“You didn’t order me one?” that unmistakable rasp of a voice asked.

My eyes snapped open to meet one dangerous woman. She had dark hair, brown skin, and olive eyes to match her very expensive-looking cocktail dress. My date belonged at the lounge of the Beverly Hills Hotel, not this storied establishment. But she couldn’t care less. This lady had confidence to spare, and she’d lowered herself to my level because she needed something from me. And it obviously wasn’t my good company.

What a letdown for you.”

This case sets him on an adventure with a twist at every turn, throwing in murders, the FBI, robot dogs, and aliens. It’s difficult to talk more about the story without giving away too much—always a challenge with detective fiction. However, its key characteristic, as I already mentioned, is its multiple twists—something that works for me sometimes, but not always. This time, it did work.

It’s a fast-paced and action-driven book, which means there’s very little character development—except perhaps for the lead character. As for the prose, this bit I particularly liked:

“The infinite void of space spread out before me, an uncompromising sea of the unknown. All those stars pulsed with the light of ancient eons, a glimpse of the past, their spark long since lost to oblivion. The breadth of the infinite was awe-inspiring, the magnitude of time an incomprehensible eternity, its emptiness all-consuming. I’d dreamed it often enough, longed for some embrace of death that would make me one with that nothingness. But being in the cockpit of our recently acquired Nebula-class frigate, I experienced something else entirely. With only the thinnest of protections keeping that abyss from swallowing me whole, I existed at the edge of the void. Death surrounded me, but for the first time in a long time, I felt alive.”

I wish there were more moments like that. Still, the book had me chuckling a couple of times—Duster Raines is an amusing narrator.

[Teresa Brock · Rating 5 out of 5]

Josh Mendoza’s Shadow of the Eternal Watcher is a gritty, genre-bending thrill ride that fuses the cerebral complexity of science fiction with the brooding intensity of noir. Set against a near-future Los Angeles simmering with corruption and interdimensional chaos, the novel introduces Duster Raines—a hard-drinking private eye haunted by his past and tormented by visions that blur the line between worlds.

What begins as a gritty detective story quickly spirals into a high-concept sci-fi narrative, as Duster discovers his alternate-universe doppelgänger: Gaius Octavius, a godlike ruler in a parallel reality. Mendoza uses this premise to explore identity, power, and the uncomfortable question of what we might become if given absolute control. It’s not just a twist; it’s a philosophical gut-punch.

Mendoza’s worldbuilding is lush and cinematic, ranging from rain-slicked cityscapes to alien dimensions bristling with robotic canines and collapsing realities. The action is fast-paced, often explosive, but never at the expense of character depth. Duster’s internal conflict—rooted in trauma and moral ambiguity—anchors the narrative in emotional truth, keeping it grounded even as the plot careens through wormholes.

I will be following this author. I would like anything like space opera (TBH I am not sure I even knew what it was) —turns out I just needed it served with whiskey, sarcasm, and a morally confused PI fighting his god-complex twin.

[Heena Rathore Rathore-Pardeshi · Rating 4 out of 5]

Shadow of the Eternal Watcher by Josh Mendoza is a wildly imaginative, gritty sci-fi noir that dares to juggle timelines, multiverses, and political conspiracies with cinematic flair. Author Mendoza crafts a rich, dystopian world where corporate empires and ancient powers collide, and he anchors it with the magnetic voice of Duster Raines—a hard-drinking, haunted ex-cop turned reluctant investigator.

The prose is punchy, immersive, and tinged with melancholy, perfectly capturing the psychological fragmentation of a man caught between worlds, both literally and existentially. There’s a pulpy, Philip K. Dick-meets-Blade Runner vibe throughout, and it works—largely due to the author's commitment to mood, atmosphere, and the undercurrent of cosmic dread.

While some moments veer into slightly over-the-top territory and the plot asks for your patience with its layered complexity, the payoff is emotionally worth it and thematically compelling. As an editor, I admire the book’s structural boldness and how it dances between gritty realism and speculative metaphysics without losing narrative control.

If you're looking for a sci-fi read that’s as psychologically charged as it is action-packed, this one’s a good pick.

[Sierra]

I'm having a lot of trouble articulating my thoughts on this book. I really enjoyed it while I was reading, but didn't feel the need to continue whenever I put it down. I didn't particularly like Duster or feel compelled by his character - everyone else in this story was much more interesting. I saw another review saying that this felt like a movie, and I fully agree. I think this is one of the few cases where a movie adaptation might be more effective than a book, and I would definitely pay money to go see it.

[Victor Neuman · Rating 5 out of 5]

I just finished Shadow of the Eternal Watcher in a single afternoon. It starts slowly and could have been a Raymond Chandler noir from the 1930s but speeds up bit by bit until you fling us screaming through the multiverse. The new bits of technology are introduced with just enough explanation. Both the heroes and villains come across as real people. I enjoyed the book and look forward to either a sequel or an entirely new offering.