• Title: The Mostly Invisible Boy (Casey Grimes 1)
  • Author: AJ Vanderhorst
  • Publisher: Lion & Co. on May 6, 2021
  • Genre: Middle Grade Fantasy
  • Pages: 307
  • Formats Available: Hardback, Paperback, & Digital
  • Rating: 5/5

Trigger Warnings: Violence

Many thanks to AJ Vanderhorst and Write Reads Tours for providing me with a digital copy of The Mostly Invisible Boy with a request for an honest review.

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The Mostly Invisible Boy Blurb

Eleven-year-old Casey is stubbornly friendly, but he’s eternally the new kid at Vintage Woods Middle School. Students look right through him—and they’re not faking. Casey doesn’t know why he’s mostly-invisible, but when he scales a colossal oak, he discovers a fortress in its branches. The forgotten sentry tree marks the border between his safe, suburban life and a fierce frontier.

Casey and his little sister Gloria infiltrate Sylvan Woods, a secret forest society devoted to ancient, wild things. Sky-high footpaths. Survival sewing. Monster control. Shockingly, people here actually see Casey—but being seen isn’t enough. He wants to belong.

Keeping his identity hidden–while struggling to prove he fits–is hard enough, but Butcher Beasts have returned to Sylvan Woods after a hundred years. Trickery is under siege. As the monsters close in, and the fearsome Sylvan Watch hunts Casey down, he and his newfound friends must unearth abandoned magic, buried at the forest’s roots…or be devoured along with everyone else, Sylvans and civilians alike.

A fast-paced middle grade fantasy/adventure book with all the monsters kids could ever hope for.

Provided by Write Reads Tours for Tour Purposes

My Review

The Mostly Invisible Boy is an excellent work of fiction. AJ Vanderhorst has the most beautiful imagination. The way Vanderhorst puts this world in your mind is nothing short of brilliant. The journey to the Sylvan Woods had me on the edge of my seat, and I wouldn’t have it any other way.

Casey Grimes is a sweet boy who nobody can see. No matter how much he tries to make people see him, they can’t. Casey feels sad and lonely in this new town where he is invisible until he comes across a giant oak tree in the woods. Casey’s mysterious babysitter urges him to visit the tree often. He even makes a new friend, one that can actually see him! Luci starts Casey and his sister Gloria on a grand adventure through the Sylvan Forest. Casey and Gloria find a great many things that are strange yet exciting.

My first reaction to Casey is how lonely he is. But, not only that, he has a special bond with his little sister. As it turns out, Gloria is also invisible in their town, and Casey never knew. This new knowledge bonds them even tighter. Casey’s demeanor is quite self-deprecating, but as he comes into his skin, he is the bravest of the brave. His new friend, Luci, helps him on his journey, and they find an unlikely ally in Robert. Robert’s first introduction to Casey is not wonderful. Though Robert does grow on you after a bit, he is rather bossy and dismissive throughout.

Vanderhorst’s creation of the Sylvan Woods puts readers right in the thick of it. I so badly want to take a bath in the caves. The whole experience gives you a renewed love for nature. The focus of the woods is the trees, and this speaks to my nature-loving heart. I want to visit this place to walk the trails and the paths through the treetops. 

This novel is full of action-packed adventure. There aren’t any dragons. But there are all kinds of other dastardly creatures waiting to torture and cause harm. When the kids aren’t running through the trees or alleys, they are battling these creatures with swords, daggers, and all sorts of cool weapons. They even have a very rare lantern that allows them to see when other forms of light won’t. 

It is my highest honor to award The Mostly Invisible Boy a full 5 out of 5 stars. This fantasy tome highlighted my weekend, and I am certain it will be for yours as well. I urge kids of all ages to read this fantastic work of imagination. I look forward to reading the next volume in this series.

About the Author – AJ Vanderhorst

AJ Vanderhorst has had many jobs, including journalist, paramedic, escape artist, and baby whisperer. One time in fifth grade, he built a traffic-stopping fort in a huge oak tree, using only branches and imagination, and slept there for a week.

Now he and his wife live in a woodsy house with their proteges and a ridiculous number of pets, including a turtle with a taste for human toes. This makes AJ an expert on wild, dangerous things—invisibility spells, butcher beasts, hungry kids, you get the idea.

He is the only author in the world who enjoys pickup basketball and enormous bonfires, preferably not at the same time. He and his family have drawn up several blueprints for their future tree castle.

Author’s Contact Links: Website | Twitter | Goodreads

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  1. Wonderful review! I just finished my read yesterday, and what I found most memorable was the relationship between Casey and Gloria❤️

  2. Amazing review Kinmie! I am reading this over the weekend and am about 1/4 of the way through so far. It’s so sweet so far and I think I’ll probably finish it today or tomorrow. I can’t wait to see what happens ☺

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