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From Cooperative Children's Book Center (CCBC)

Circle is playing hide and seek with her friends Triangle and Square and insists no one hide in the cave behind the waterfall—she’s afraid of the dark. Still, she goes inside when it’s clear that’s where Triangle must be. The deeper into the cave Circle goes, the darker it gets, until only her eyes are visible. When a second pair of eyes appear in front of her, she voices her frustration at Triangle, then apologizes: “You are a good friend.” A third pair of eyes appear behind her. “Thanks!” says Triangle. In a picture book full of humor, but also a little tenderness and a big surprise, the expressive eyes in the muted digital, graphite, and watercolor illustrations speak volumes. Reunited outside the cave, the three shapes imagine what other shape might be inside the cave; the book’s open ending invites children to do the same in this companion to Triangle and Square. (Ages 3–8)

CCBC Choices 2020 © Cooperative Children's Book Center, Univ. of Wisconsin - Madison, 2020. Used with permission.

From Horn Book

July 1, 2019
While playing hide-and-seek with Square (Triangle; Square), Triangle breaks Circle's rule about not hiding behind the waterfall. Annoyed, Circle follows him into a dark cave until only expressively drawn eyes are visible. An unknown third pair causes the friends to flee, with philosophical Circle wondering what shape it was. Klassen's understated work with light, shadow, and texture in the graphite, watercolor, and digital illustrations carries Barnett's highly entertaining story full...circle.

(Copyright 2019 by The Horn Book, Incorporated, Boston. All rights reserved.)

From Horn Book

March 1, 2019
While playing hide-and-seek outside, Circle (from Square, rev. 7/18; companion book to Triangle, rev. 5/17) has one firm rule: No hiding behind the waterfall. Square doesn't mind, but Triangle pushes back; and when Circle opens her eyes, Square is pointing, tattletale-like, in the direction of the waterfall. Behind the waterfall?rendered simply and stunningly as a cascading, textured, icy-aqua sheet?lies a cave; Circle enters, annoyed. It gets darker and darker, and Klassen's graphite, watercolor, and digital illustrations respond accordingly (and remarkably), as shadows gradually obscure the scene; soon all we see is a pair of the illustrator's trademark expressively drawn eyes. Then we see two pairs of eyes, and Circle lets loose: Triangle?Why do you always break all the rules??Why do you always spoil our fun??Why are you such a bad friend? Harsh, Circle! She apologizes right away, but now there are three pairs of eyes?with the third belonging to Triangle, standing behind Circle. Who was Circle yelling at? Freaked out, the friends flee the cave, the progression from dark to light in the art being just as impressive as on Circle's way in?back through the waterfall. Safely outside, Circle turns philosophical: You know?that shape in the dark might not have been bad. It might have been a good shape. We just could not see it. The friends close their eyes to imagine what was in the cave, and Barnett's straightforward text invites readers to do the same: If you close your eyes, what shape do you picture? Subtle it's not, but the message is highly entertaining in its delivery, and Klassen's understated work with light (and the absence of it), shadow, and texture carries the story full?circle. elissa gershowitz

(Copyright 2019 by The Horn Book, Incorporated, Boston. All rights reserved.)

From School Library Journal

February 1, 2019

PreS-Gr 2-Square and Triangle are back with a new adventure and their friend, Circle. In this story, Circle invites his pals to play a game of hide-and-seek near her waterfall. Circle's only rule is "no hiding behind the waterfall." It is dark, unknown, and scary behind the waterfall. But Triangle, who isn't scared of the dark, goes there, forcing Circle to follow into the dark unknown. Triangle is soon recovered, but they also meet another shape in the darkness. It might have been a good shape, it might have been a bad shape, but they could not see it. So they each close their eyes and imagine the shape it could be. If you close your eyes, what shape do you picture? The short sentence structure, quick-moving plot, and simple illustrations make this installment in the creators' shape trilogy just as much of a page-turner as the previous two books. VERDICT Sure to please fans of Square and Triangle, this entry is just as likely to draw in plenty of new readers, too. Recommended. -Elizabeth Blake, Brooklyn Public Library

Copyright 2019 School Library Journal, LLC Used with permission.

From Kirkus

January 15, 2019
Circle, Square, and Triangle play a game together with surprising results.The three shapes are friends. Illustrator Klassen's watercolor, graphite, and digitally created illustrations are evocative in their muted palette and spare presentation, the shapes drawn simply, with white, rounded-off oblongs for eyes whose black pupils move back and forth to show action and emotion. One day, Circle suggests a game of hide-and-seek and tells her friends not to hide behind the waterfall, because it is dark. When Circle finishes counting, Square has not moved; he tells Circle, "Triangle went behind the waterfall." Circle goes to find him, and as she delves deeper, the double-page spreads darken to solid black until only Circle's white oblong eyes are shown. She sees one set of eyes and begins to upbraid Triangle--and then a third set. Turns out that is the set that belongs to Triangle, and when the two realize they don't know the other, they rush away in a fright. Safely back in the open, Circle wonders what shape was in the dark and, reflecting on her fear, realizes that the shape wasn't necessarily "bad" just because she couldn't see it. While the implied message of the story is a vital one in this xenophobic age and its subtle delivery and imagery encourage further exploration, the story's final page veers off, asking readers to picture a shape rather than delivering a conclusion. Worthy and allusive but with a possibly frustratingly oblique ending. (Picture book. 4-8)

COPYRIGHT(2019) Kirkus Reviews, ALL RIGHTS RESERVED.

From Booklist

January 1, 2019
Preschool-G Barnett and Klassen's Shape trilogy is completed with the arrival of Circle, who invites Square and Triangle for a game of hide-and-seek near (but not behind) her waterfall. Both agree, but, of course, Triangle disregards Circle's one rule and hides exactly where he shouldn't. Resigned, Circle enters the dark cave behind the falls to find her friend, venturing deeper and deeper until it's pitch black and all the reader sees are Circle's eyes in the darkness. Finally, another set of eyes appears, but when Triangle's voice comes from an entirely different part of the cave, Circle and Triangle bolt for the exit. Back in the safety of daylight, Circle ponders what the shape in the darkness might have been, inviting her friends and readers to do the same. In typical Barnett-Klassen style, humor and light philosophical musings mingle to form a story that will entertain children and adults alike. Because much of the story takes place in darkness, readers are called upon to use their imaginations, making this oddball friendship tale an off-kilter treat. HIGH-DEMAND BACKSTORY: If you don't order extra copies of this dynamic duo's latest, their fans will get bent out of shape.(Reprinted with permission of Booklist, copyright 2019, American Library Association.)