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Imaginary Numbers

(InCryptid #9)

4.41  ·  Rating details ·  213 ratings  ·  60 reviews
The ninth book in the fast-paced InCryptid urban fantasy series returns to the mishaps of the Price family, eccentric cryptozoologists who safeguard the world of magical creatures living in secret among humans.

Sarah Zellaby has always been in an interesting position. Adopted into the Price family at a young age, she’s never been able to escape the biological reality of her
Mass Market Paperback, 448 pages
Published February 25th 2020 by DAW Books
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Thanks to Netgalley and Berkley for providing me with an advanced copy in exchange for an honest review.

I don't know how to write this review. I'm just in awe of Seanan's ability to change up the main character so often and still keep all the storylines straight and the character voices so strong.

CUCKOOS. That's right, what we've all been waiting for. More lore, more interactions, more HOLY CRAP CUCKOOS. More Sarah, who, after the events of the beginning of the series, has been mostly sitting
Lisa Wolf
It makes me so happy to have a new InCryptid book in my hands, especially since I won this one in a Goodreads giveaway, which pretty much never happens for me! THANK YOU, GOODREADS!

In Imaginary Numbers, the ongoing InCryptid series turns to two new point-of-view characters, Sarah Zellaby and Artie Harrington. Sarah and Artie are both members of the sprawling Price-Healy clan, a group of cryptozoologists dedicated to protecting non-human species from the persecution of the deadly Covenant, and
Feb 23, 2020 rated it it was amazing
Shelves: arc-paper
4.5 Stars bumped to 5 Stars because Math and Xenobiology are just my jam and both have starring roles in this one.

Sarah Zellaby is a Cuckoo, or more correctly a Johrlac psychidolos. Johrlacs are similar to parasitic wasps and got called cuckoos for their habit of leaving their young for others (humans) to raise. How do humans get fooled by these baby Johrlacs? With their big blue eyes, soft, pale skin, and human-appearing features, Johrlacs are mammals but are literally heartless. All males look
Feb 12, 2020 rated it really liked it
*Source* Publisher
*Genre* Urban Fantasy
*Rating* 4.0


Imaginary Numbers is the Ninth installment in author Seanan McGuire's InCryptid series. If you have not started reading this series yet, InCrypid is a witty urban fantasy series featuring an eccentric family of cryptozoologists who act as a buffer between the humans and the magical creatures living in secret around us. The main focus is on the Price, Baker, and Nealy families who have vowed to protect peaceful crypid's from humanity
From the blurb: But there are cuckoos everywhere, and when the question of her own survival is weighed against the survival of her family, Sarah’s choices all add up to one inescapable conclusion.

This is war. Cuckoo vs. Price, human vs. cryptid…and not all of them are going to walk away.

Well now I’m nervous! I love this series and I definitely don’t want any of the family to die
Jan 31, 2020 rated it it was amazing  ·  review of another edition

Review to be posted closer to publication date

[EDIT]: Proper review aka what on earth was that ending? aka I am I supposed to survive the wait for the next one?

"Math is everywhere. Math is everything"

Going into this book I had zero expectations – you know, apart from it having cryptids and being an awesome story, it’s a Seanan McGuire book, so, some things are assumed.

But, I didn’t know what to expect. When we first switched to Alex, I was pouting because I loved
keikii Eats Books
Feb 27, 2020 rated it it was amazing
To read more of my reviews, check out my blog at keikii Eats Books!

Warning: Cliffhanger (I didn't know that was possible with Seanan McGuire...)
"Why would we chill, exactly?"
"Because you're the good guys," said Mark.
"Anyone who thinks good means chill needs to spend more time with my family," said Elsie."

New InCryptid, new perspective! This time it is Sarah Zellaby, and boy did my excitement for this book jump up like 150% when I found that out. This really was great. Maybe
Feb 14, 2020 rated it it was amazing
I was given a free online galley of this book, in return for an unbiased review.

I have been waiting for an Incryptid book focused on Sarah, the non-human psychic member of the Price clan, and Seanan did not disappoint. Sarah might be my favorite POV protagonist in this series, thus far, as her unique way of looking at the world added a fresh dimension to the cryptozoology franchise. Seanan expands the Incryptid world in this entry, giving us more insight to the mysterious Cuckoo species, of
Oct 15, 2019 rated it it was amazing
Shelves: fantasy
10-15-19. Comment based on pre-release synopsis: er, ohoh. I’m guessing poor Sarah :( I -like- Sarah.
Edit after reading, 2-27-20: well, that novel (and that novella) were terrific. Anticipating the sequel!
Colleen Corgel
The Prices are back in this new urban fantasy adventure novel set in the InCryptid universe. This story focuses on Sarah, who is back on her feet after feeling like she'd been broken for most of the five years (which is about the last 6 novels or so). She gets to confess to her adopted cousin, Artie, the reclusive half Incubus, and finally get's to see the rest of her favorite Prices. But of course, in the world of crypto-zoology, there's very little time to rest. When she realizes that the ...more
Feb 21, 2020 rated it it was amazing
Find this and other reviews at The Reader in Indigo

Sarah's book! IT'S SARAH'S BOOK!

That's literally what I shouted (yes---out loud, like a lunatic) when a random package from Penguin Random House showed up on my doorstep, containing an ARC and a paper telling me I'd won one of those contests that I always enter but never, ever win, but somehow managed to win this time, and can you think of a more perfect day than that? Of course you can't. Don't lie.

(But I lied, gentle reader, because it turned
Feb 25, 2020 rated it really liked it
Disclosure: I received this book for free in exchange for an honest review. This does not affect my opinion of the book or the content of my review.

I admit to being surprised by Imaginary Numbers. It’s been quite a while since Sarah saved Verity and I wasn’t quite expecting her story. Now, if I’d been following Seanan’s social media or paid attention to remembered the blurb... (insert eye-roll emoji here)

ANYWAY. Imaginary Numbers is 100% cuckoo, and boy oh boy are they (more than just) a bit
Christina (A Reader of Fictions)
Ever since I found out this book would be starting a new arc about Sarah, I was thrilled. She's been a favorite since the first book, and I was excited to finally get the deets about her an Artie. Imaginary Numbers does not disappoint, and I would rank it among my favorite InCryptid books.

Sarah's such an interesting character, and this book really dives into what it's like being Johrlac/Cuckoo, both for a unique one like Sarah and for others. The Cuckoos have been creepy in the background for a
Dec 20, 2019 rated it it was amazing
Shelves: 2019
I was lucky to receive an ARC from DAW Books in a giveaway—thank you so much!

Okay, first things first: if you haven’t read any of the InCryptid series before, this is NOT the book to start with. You won’t know who many of the major characters are, or why what’s happening to them is important. I highly suggest starting with Discount Armageddon and reading through from there; it’s so worth it! With that disclaimer out of the way...

I’ve been waiting for Sarah’s book for a long time, and so has
Feb 25, 2020 rated it really liked it
Follow the Lady:
I started with the novella in the back of the book because that actually takes place between #8 and #9 in the timeline. In this novella, Annie and her friends run into Grandma Alice on their way home, and tell her about what happened with the crossroads in the previous book, and what they learned from it. This was a great little story, pretty much exactly how I imagined that conversation going. I love Alice and can't wait for her to get her own book (I think in 2022, after one
Imaginary Numbers, book 9 in the InCryptid series, marks the start of a new arc; and we're on to Sarah, cuckoo and gateway to an exceptionally intriguing mystery.

The cuckoos have appeared in plenty of the forty-something Incryptid works, and not just because the Price family are willing to adopt just about anyone. No, usually they're a The Silence-esque threat that pops up where least expected, because just like a black hole you usually have to spot them using the vacant places they leave
Feb 18, 2020 rated it really liked it
As expected, this is another great entry into Seanan McGuire's Incryptid series. Even more then McGuire's other series, this is one where each book builds on the others and makes the series more and more engaging. As we get to know more and more members of the extended Price family the stakes keep rising, both for the character and for those they have vowed to protect.

"Imaginary Numbers" is the first book in the series to have non-human narrators, splitting the story between Sarah and Artie.
Leslie Finn
Feb 28, 2020 rated it it was amazing  ·  review of another edition
Oh joy, another Incryptid novel

These books are a joy. It's always a celebration when a new one comes out. I've been following this series since the beginning. Finally, finally we get a story featuring Sarah Zellaby, the cuckoo-girl. Sarah has now healed enough to head to Portland, Oregon, to reconnect with the family after five years of recovery. Those following the series know she was injured helped Verity elude the Covenant of St. George. I'm not going to give any spoilers here as everyone
Feb 24, 2020 rated it really liked it
Seeing that a book is the ninth in a series would give readers a pause, but the nice thing is this one keeps changing POV characters. Sarah a cousin of the of the previous POV she is not related by DNA but adoption and the only reason it mattes is that she is a cryptid. Her species look alike and use telepathy to control people around them. Sarah was raised being told it was wrong. She does use her powers and early in the series she burned herself out saving her cousin. Five years later, Sarah ...more
C.L. McCollum
Feb 28, 2020 rated it really liked it
Trigger Warnings: Discussion of abandonment of children leading to eventual adopted family deaths, discussions of torture of enemies for information, threats of physical violence.

Oh man I LOVED this installment of the InCryptid verse. Sarah has such a fabulous POV and it's awesome to see one of the true cryptids get a POV this time. Plus all the math ever, but in a way that felt very accessible, if that makes sense? I loved getting glimpses of family dynamics we hadn't caught in previous books
Harald Koch
I have a lot of problems with this book. I'm still trying to decide whether I like it more or less than Discount Armageddon.

- It's a *lot* of info dump, disguised as internal monologue. I hate info dumps, even when they're written as well as Seanan writes.
- If I have to read about how (Great) Grandma Francis was immune to cuckoos one more time I will metaphorically throw the book at a wall. I mean really - STOP TELLING ME, THE READER, THIS MINOR PLOT POINT OVER AND OVER AGAIN.
- This book ends in
Alex Can Read
Feb 26, 2020 rated it it was amazing
I think Sarah is my new favorite narrator of the InCryptid universe. She's not human and while she's still very clearly a Price, her narration is naturally very different from the other Prices' narrations. In Imaginary Numbers we learn a lot about Cuckoos as a species which was very exciting to me. I loved the deep dive into the species history and biology.

McGuire brings up an interesting thought experiment within the story - when two cultures have different expectations and customs that are
Darlene M
Feb 24, 2020 marked it as to-read
A fabulous addition to Seanan McGuire's InCryptid series, Imaginary Numbers is Sarah Zellaby's story. Sarah is flying to Portland, Oregon to spend time with family and see Artie, also to find out if she has recovered from the incident in New York City. When she arrives in Portland she senses another Johrlac or cuckoo, which is not a something she was expecting and which could be dangerous to her and to her family. Sarah leaves the other Johrlac unconscious in the airport restroom, and tries to ...more
Kathryn Walby
Feb 27, 2020 rated it it was amazing  ·  review of another edition
Disclosure: I have been obsessively reading everything Seanan McGuire writes for the last several years; I pre-ordered Imaginary Numbers last summer when it was first listed on Amazon, and started reading on release day.

This book is yet another one that I devoured over the course of one day, and can't wait to go back and read again. Ms. McGuire does a fantastic job evolving the characters so that even when the behavior is surprising, the reader can appreciate the overall arch of development -
Dec 27, 2019 rated it it was amazing
I received an ARC of this book as part of a Goodreads giveaway.

Go Big or Go Home

Usually, Seanan kind of eases us into a new arc with a local issue and some romance, then she escalates. I guess she didn't find that necessary when 1. We'd already gotten some Sarah perspective chapters back in book two and 2. We already knew that Sarah and Artie were in love. So its like instead of sending us on a fun cryptid royal coaster, she shoved us off a cliff, then called down "There's a parachute around
Holy crap. I just finished this and, wow, it packs a *punch*. If you read Dresden Files, you'll get this: it has a bigger punch ending than Changes. Yeah, I'm calling that. I about threw my phone across my office.

As always, McGuire weaves her story well, bringing us in with the family emotions, then using that to hit us hard. I felt like I was on a rollercoaster in Lowryland, with all the highs and lows. And the Aeslin mice made me want to cry :(

If you're a fan, you won't be disappointed by this
Feb 25, 2020 rated it it was amazing
I got free arc of the book by the publisher for reviewing this book.

If you enjoy watching those cryptid paranormal shows and love reading urban fantasies with science fiction and horror interwoven in them, you will enjoy this book. Flavored like Invasion of the Body Snatchers and those sci-fi movies of the 50s and early 60s, added with dashes of cryptology, Imaginary Numbers is an edge of your seat storyline that hooked me to the end.

Read the rest of the review at
Jan 31, 2020 rated it it was amazing
I love the InCryptid series and was thrilled to get an Advanced Reading Copy. I love learning more about Johrlac/Cookoo and Lilu/Incubi. The book has points of view from both Sarah and Artie which is fun. I also like day to day views of the mice (I absolutely adore the mice). The story is strong with lots of twists. The ending is a bit of a cliff-hanger (Dang it Seanan). I also enjoyed the novella but suggest reading it before the book (poor Sam has little idea of what he is getting into, James ...more
Dec 26, 2019 rated it really liked it
Thank you for the ARC, Goodreads and Seanan! I was so excited to read the latest InCryptid book. This was a really solid addition to the series, and fleshed out several characters who deserved more screen time. It did feel much more focused on character development than some of the previous books; fewer things, well, *happen* in this book than in a standard Annie or Verity book. I also have my qualms with the ending of the book (no spoilers here). Overall, really enjoyed; this series keeps ...more
Feb 18, 2020 rated it really liked it
I'd stopped reading the InCryptid series after I wasn't a fan of book 4, but I'm so glad I picked this series back up! Sarah and Artie's story is intense (I dont want to say too much) but it has Ms McGuire's witty humor and lots of fantastic creatures that denotes this series' theme. The backstory on the Cuckoos is fascinating, it turns out I love the Price family still, and oh, how I'd missed the Aeslin mice! This has a cliffhanger ending, so I'm definitely going to be on tenterhooks until the ...more
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Hi! I'm Seanan McGuire, author of the Toby Daye series (Rosemary and Rue, A Local Habitation, An Artificial Night, Late Eclipses), as well as a lot of other things. I'm also Mira Grant (, author of Feed and Deadline.

Born and raised in Northern California, I fear weather and am remarkably laid-back about rattlesnakes. I watch too many horror movies, read too many comic books, and

Other books in the series

InCryptid (10 books)
  • Discount Armageddon (InCryptid, #1)
  • Midnight Blue-Light Special (InCryptid, #2)
  • Half-Off Ragnarok (InCryptid, #3)
  • Pocket Apocalypse (InCryptid, #4)
  • Chaos Choreography (InCryptid, #5)
  • Magic for Nothing (InCryptid, #6)
  • Tricks for Free (InCryptid, #7)
  • That Ain’t Witchcraft (InCryptid, #8)
  • Calculated Risks (InCryptid, #10)
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