Very unique and entralling. Vivid emotions and a very layered story. Incredible debut book!

Thanks Netgalley, Mariner Books for this ARC!

Thank you to Mariner Books and NetGalley for the e-ARC.

I'll be honest, it was the title that grabbed my attention. However, it was not a bad book, but also not a good book - at least for me. I found myself compelled to finish because of my commitment to review it; had it not been for that it likely would have end up on my "wanted to like but" and "did not finish" shelves. It just was meh for me. I was not invested in the characters, both modern day and the historical characters. The speculative fiction aspect with the defractor was underwhelming. So a generous 3-stars.

Beautifully written book that weaves Salvadoran history with queer romance and lots of, “what if” questions. I liked the combination of the multiple timelines and the magic component, but it got a little muddled for me in the middle (whose timeline or if it’s the detractor storyline). Not sure if something could’ve been done with the format to help clarify.

2.5 - Thank you so much to Mariner Books for sending me a complimentary copy of this book!

This book is out now!

Magical realism and I have a complicated history. Sometimes I have no issue with it and other times such as this I struggled. A book friend had recently read this and I trusted her judgment with and kept going. But honestly I wish I had DNF.

I really wanted to enjoy this more and maybe if I fully did tandem reading on this perhaps it would have landed differently with me? I struggled with the Defractor and the universes happening seamlessly within that particular timeline. And when I thought I was following something would happen and then I'd be like wait what was that.

I just think this book might have just been too smart for me. There are plenty of fabulous reviews and I would check out others who loved it to help make your decision on reading this. I had not read Reyes first book which I still would read as well as give him a try again. I didn't mind the writing itself but perhaps the realism just was a little to much for my taste.

4.5 stars. A pair of Salvadoran American students explore their troubled history and test the limits of their relationship by using an experimental device called the Defractor. The machine allows its users to view alternate realities. Through the machine’s use, the students discover a connection to two star-crossed revolutionaries during El Salvador’s devastating civil war. This book takes readers on an emotional journey through dramatic family histories, while emphasizing the love that sustains its members through everything.

Thank you NetGalley and the publisher for the ARC. Apologies for the late-ish review!

I enjoyed this book. I learned a lot about the Salvadoran Civil War, and the concept of a Defractor (which allows people to view alternate life paths) was fascinating. The varying timelines, alternate lives, and multiple characters got a little confusing, but I figured it out eventually.

The love story between Rafael and Neto was quite powerful, although the amount of time we got to see them together was extremely limited. The love story between Ana and Luis was very sweet too, just a little muddier, and again, kind of confusing.

A solid (but not amazing) debut novel.

Archive of Unknown Universes by Ruben Reyes Jr. (book cover is in image) is set in the two different timelines of El Salvador in the 70s and 80s and 2018 Boston and El Salvador in the present day. It follow two couples Neto & Rafael and Ana & Luis.

In the present day Ana and Luis use the Defractor, a device that allows users to see the alternate paths their lives having visibility into what could have been. Covering the themes of love, loss, identity and generational trauma, this book was an engaging read and I highly recommend it.

Thank you @marinerbooks and @netgalley for the opportunity to read this ARC. All opinions are my own.

Pub Date: Jul 01 2025
Rating: 4 stars

#MarinerBooks
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Archive of Unknown Universes is a quiet, beautiful novel about grief, memory, and the lives we might have lived. The premise is surreal—accessing alternate versions of yourself—but the emotions are deeply human.

The writing is poetic, the pace slow but rewarding. At times the worldbuilding felt a bit vague, but that ambiguity adds to the dreamlike atmosphere.

✨ Review ✨ Archive of Unknown Universes by Ruben Reyes Jr.

Thanks to Mariner Books and #netgalley for the gifted advanced copy/ies of this book!

This one is really difficult to describe - you'll just have to read it yourself lol.

There's a dual timeline that switches between 1978 Havana / Central America and 2018. But maybe this is really a triple timeline because it flips between two alternate universes in 2018 – one if the Salvadoran revolution failed and one if it succeeded. It has the same characters but with very different outcomes. In many places, it was super confusing - I was constantly flipping forward and backward to reference – I recommend a printed copy to make this easier.

Most compelling was a look at queer love in 1978 Central America -- the hope and beauty juxtaposed with the dangers the characters faced. The love letters exchanged by Neto and Rafael were really lovely. This is where this story shone.

At the same time, it had such incredible writing and it produced this fascinating blend of literary fiction, sci fi, and historical fiction. I was so compelled to keep coming back and working through this, even when it was challenging. It was such a beautiful meditation on love, history, and why we fight.

⭐️⭐️⭐️⭐️💫
Genre: literary fiction + sci fi elements
Setting: US + Cuba + El Salvador + Nicaragua
Pub Date: Jul 01 2025

Just when I thought magical realism had been beaten to death by formulaic writers (think Isabel Allende), along comes Ruben Reyes Jr. and his Defractor! This is magical realism for the 21st century. I'll definitely be looking forward to more from Ruben.

A strange but lovely speculative novel that hinges on a technology that allows the user to see alternative pasts for themselves. A page turning adventure with some fun absurdist quirks (Alanis Moresette and Avril Lavigne as interfaces, for example). Wholeheartedly original.

This book packed so many layers into its slim 288 pages. Beautiful and devastating, and terrifically smart. Experimental without coming off as pretentious and turning me off. Reyes’s prose is phenomenal, but I think it’s the three-dimensional humanity of his characters that makes <i>Archive of Unknown Universes</i> a modern classic. Everyone is real and everyone is flawed and written with incredible empathy. And there is just SO MUCH here. A revolution is won or lost. A man is killed or recovered from captivity. A boy and a girl (but which boy?) find a Bible and a stash of letters. Two men are forced apart—by death, by the world, by their own doubts—or find one another again. And the universes seen are at once vastly different and so similar, so understandable to one another.

And hell, I even learned something. I didn’t know much about El Salvador’s history before reading this book. I’m ashamed to admit I had to go to Wikipedia to confirm which of the universe branches we happen to reside in (neither of the main branches, as far as I can tell: the revolution was successful, but Oscar Romero was assassinated in 1980 and this was in fact one of the catalysts.) It may be time to go down a rabit hole and get better informed.

I’m also low-key fascinated by a phenomenon I’ve been seeing lately examplified in this book: novels which are fundamentally magical realism, but their speculative element is framed via science fiction trappings. I’ve seen this in <i>The Other Valley</i>, and <i>The Poppy Fields</i> as well. If I was still a baby lit major full of energy, I feel like there’d be a paper in this. As things stand, I’ll just say I liked <i>Archive</i> by far the best of the three.

I loved this book. I’m almost sad to be done with it, because I can’t savor it any more. But hey, maybe in another universe, a very similar other universe, I’m still savoring those few extra pages.

Thank you to NetGalley and Mariner Books for the free ARC in exchange for an honest review. All opinions within are my own.

Have you ever wondered about the myriad turns your life could have taken if a certain event did not take place or if your family made different choices? If you made different choices? What if you were able chase these ghosts by using a machine that allows you to look at other possibilities?

That is the story that Ruben Reyes Jr. explores in his debut novel Archive of Unknown Universes.

Alternating between timelines, universes and people, we are introduced to primarily four characters who participated in or were impacted by the Salvadoran Civil War.

The story takes us from Los Angeles to Cuba to Nicaragua to El Salvador to unravel how these narratives play out.

I previously enjoyed Reyes’ short story collection. In Archive of Unknown Universes he continues to deliver flawed, unforgettable characters and shine light onto Salvadorian history.

I'd recommend this to readers who like reading historical fiction, enjoy speculative elements, and like to read about messy relationships.

Thank you to Netgalley and Mariner Books for an advanced readers copy !

I absolutely love finding novels about pieces of history that I know nothing about. I knew next to nothing about the Salvadoran Civil War before reading this book, and walked away with a heart full of admiration for this group of people - the revolutionaries, the immigrants, the people who stayed.

This was really so beautiful. The prose was captivating and lyrical. I love the exploration of things as they might have been - it was bittersweet and wonderful. And the theme of honoring histories, of people living on even after they are gone, really resonated with me. The love between Neto & Raefael is also so real and raw, I was invested in them all throughout the book, in every universe.

Thank you so much to NetGalley and the publisher for this ARC!

I found this book a little confusing to follow. We follow two different timelines, Ana and Luis, and Neto and Rafael. I found myself enjoying Neto and Rafael's story more and almost wish that they were the main story line. This book would also jump to different point of views and I found myself struggling to keep up with who's POV we were following. I found the history that this book references incredibly interesting and I wanted more of that. Overall this was a good book.

While I found this book to be flawed in ways hard to ignore, it also cemented Ruben Reyes Jr. as an author whose career I’ll continue to follow with great interest. He so clearly possesses great talent as a crafter of sentences, and his depiction of both love and longing in this book was remarkably evocative. That said, I found the speculative aspects (basically anytime the Defractor came up) at best confounding and at worst kind of annoying. It felt shoved into the story in a way that broke my immersion, and the jokey bits fell very flat. Ultimately though, part of my annoyance was from a desire to return to the characters that Reyes had so deftly drawn.

In ARCHIVE OF UNKNOWN UNIVERSES Ruben Reyes Jr. has crafted a beautifully layered novel that blends family history, queer romance, and speculative tech in a story that feels both deeply personal and refreshingly inventive.

The story follows Ana and Luis, two college students whose summer trip to Cuba becomes a journey through untold family secrets, thanks to a sci-fi twist involving a device called the Defractor. The device allows them to view alternate versions of their lives. The discovery of an old Bible leads them to uncover the hidden past of Luis’s great-uncle Neto, whose story during El Salvador’s civil war becomes a powerful thread throughout the novel.

The narrative is told with energy and emotion, and shifts between present-day Havana, historic wartime Central America, and other imagined parallel timelines. Reyes's writing is deeply engaging and emotional, and it brings each character to life with sharp dialogue and fast-moving scenes. The writing stays grounded in sensory details and heartfelt moments that make the more surreal elements feel believable and human.

What makes this book stand out is how relatable it feels. Reyes makes the relationships messy and emotionally raw without feeling overwrought. ARCHIVE OF UNKNOWN UNIVERSES is a moving story that is full of heart, and readers will surely keep thinking about it long after they finish reading.

This book is for you if you've ever felt overwhelmed thinking about all the little ways your life could have been lived differently.

Ruben Reyes Jr. tells a heartfelt story about a search for meaning among alternate timelines. Characters gather bits and pieces of themselves (and their loved ones) while learning about the past and tracking the past's ripples into the present. We see how a life is made up of simple choices but also that it's not often helpful to obsess over which decisions were the "right" ones.

The characters were realistic and loveable, the settings were vibrant, the relationships tender, and the Defractor... a slightly ominous sci-fi centerpiece with it's mysterious workings and peppy interlocutors.

4.25 ⭐️. A really cool concept and a great story about love in all kinds of different forms. This book tackles love among lovers, family, friends, comrades, old flames, and dying flames. The parrellel timeline stuff was a bit confusing at the beginning, but once it gets going it’s a great way to show the way all of these relationships played out or could play out. Thank you so much to NetGalley and @marinerbooks for the ARC, and I’m very excited to meet the author at an upcoming book festival

very interesting alternate timeline - type story emphasizing two timelines and two connected families from alternate universes. 5 stars. tysm for the arc.