The Cousins Intrepid-Into the Infinite Unknown

by Greyson Peters

Zane and Flynn Harper are two ordinary teenagers who’ve had their share of hard knocks. But when a mysterious envelope opens a doorway to an entirely new galaxy, nothing will ever be the same.

The Union of Seventy-Seven Planets faces a new kind of mental illness as plague. As entire worlds spiral into chaos, an ancient starship—and its unexpected new crew—may be the Union’s last hope. But can two untested boys from Jasper Creek, Tennessee really carry the weight of peace and order?

This is the first full entry in the seven-book series The Cousins Intrepid.

561 pages, Kindle Edition

Published August 13, 2025

Reviews

[John · Rating 4 out of 5]

A good read. Like the way the story and characters stayed true

stayed true to their principles. Very little to no real violence but still Captivating. Very good with Mental health issues,

[Robin Ginther-Venneri · Rating 5 out of 5]

The Cousins Intrepid: Into the Infinite Unknown
By: Greyson Peters
Publisher: Greyson Peters
Published Date: August 13, 2025
ASIN: B0FGZJT28F
Page Count: 463
Reading Age: 8 – 18 (but adults with spacefaring daydreams may apply)
Star Rating: ⭐️⭐️⭐️⭐️⭐️

Equal parts space opera, heartstring-tugger, and "what the heck is going on?" The Cousins Intrepid is a bold debut that dares to ask: what if emotional baggage could destabilize entire planets? Fun, thoughtful, and just the right amount of strange. Book 2 better be on the way.

What Did I Just Walk Into?
Ah yes, just your average Tuesday: two small-town teens stumble through an envelope (???) into a galaxy-wide mental health crisis, get handed the keys to a relic starship, and are somehow the only thing standing between seventy-seven planets and total collapse. Sure, okay. Why not.

Here’s What Slapped:
Worldbuilding that deserves its own travel brochure. You’ll want to vacation on at least three of these planets well, the ones not in full-scale existential meltdown.
Zane and Flynn: Tennessee charm meets space soap opera. Equal parts “Why are we here?” and “Who let us have responsibility?”
Sci-fi with feelings. You’ll laugh, you’ll sigh, you’ll question the galactic healthcare system.
A plot twist that made me shout “excuse me?” at an empty room. In a good way.

What Could’ve Been Better:
The first few chapters ease you in with all the urgency of a Southern porch swing. Stick with it. Once the story goes interstellar, it goes.

Warning: you might find yourself emotionally attached to a spaceship. Or a sentient spreadsheet. Hard to tell which was more effective.

Perfect for Readers Who Love:
Sci-fi that doesn’t require a PhD in quantum mechanics to enjoy
Coming-of-age stories with extra planets
YA protagonists who are awkward, brave, and probably winging it
Narratives that blend chaos, heart, and just enough weird to keep you turning pages

Reviewed by Robin for Robin’s Review

[Lili_Recs · Rating 5 out of 5]

4.5 stars

Really good book!
I really enjoyed reading it. The story was well written, complex, and new.
It gave off old sci-fi movie vibes but even better! (Did that make sense?).

The characters were original and human. I found it easy to connect and get attached to them. Zane and Flynn were GREAT characters.

This book addressed mental health really well.

The world was so cool! I really enjoyed reading about each planet, they were all unique and not stereotypical. My favorite was probably Luminite (I think that's what it's called? I'm sorry if I got it wrong 😭). I loved learning about their culture, their face paint, how it was created, etc. Super cool!
Honestly, everything made sense! I wasn't confused about any part of the book. Everything flowed smoothly. The story was NOT predictable. The only predictable part is that they're heroes and fighting against a villain. I was actually surprised at the direction it was going in sometimes and some parts even made me laugh.

Really excited about the series! Can't wait for the rest to come out!


I read this book as an ARC. All thoughts are my own. Thank you to @theauthorintrepid for the copy


TW: Suicide, Loss of loved one, grief, mental illnesses
Language - ❌
Spice - Level 1 - Non-physical romance: flirting and feelings without any physical interactions
Violence - 🔪 - Fantasy Violence

[Tanya · Rating 5 out of 5]

They are about to have their lives turned upside down when a message arrives. The worlds are being plagued by a mental disease and it seems they may be the ones to prevent war and get peace. They have no idea where to start or even what to do.msee what is going to happen for them
I received an advance copy from hidden gems and a great adventure read

[emeraldragonlady (Maddie) · Rating 4 out of 5]

This was fantastic! The best way to describe this is what if Star Wars & Star Trek had a baby? This would be that book. It has the government ideal system from Star Wars and the save-the-world science from Star Trek. All the characters are relatable, the story is well thought through and fleshed out, and the author is very upfront with the trigger warnings. The author also gives you some background at the end on where and how he drew up inspiration for this book. This is a fantastical sci-fi for young adults! Highly recommend for all.

[Marisa · Rating 5 out of 5]

I read this as an ARC, the opinions expressed are my own:

This debut novel by Greyson Peters unexpectantly drew me in. I am not typically a SciFi reader but I thoroughly enjoyed this book.

The first two chapters were a little slow but it was necessary to introduce the two main characters appropriately. After that the adventure took off, and I was sucked in!

I loved the author’s descriptive writing. He helped paint the worlds so vividly in my mind, it was easy to transport myself into the book. Very good character development as well. I love a book that gives depth to its characters.

This is book one of a seven book series and I cannot wait to get my hand on book two (book one hasn’t even officially been released yet). This is an easy add to TBR!