About the Author

Mac Barnett, the 2025–2026 National Ambassador for Young People’s Literature, is a New York Times best-selling author of stories for children. His work has been translated into more than thirty languages and sold more than five million copies worldwide. Mac Barnett’s books have won many prizes, including two Caldecott Honors, three New York Times/ New York Public Library Best Illustrated Children’s Book Awards, three E. B. White Read-Aloud Awards, the Boston Globe–Horn Book Award, Germany’s Jugendliteraturpreis, China’s Chen Bochui International Children’s Literature Award, the Netherlands’ Zilveren Griffel, and Italy’s Premio Orbil. He is the cocreator, with Jon Klassen, of the Substack Looking at Picture Books, as well as Shape Island, a stop-motion animated series on Apple TV+, based on their best-selling Shapes series of picture books. Mac Barnett lives in Oakland, California.

Jon Klassen is the author-illustrator of I Want My Hat Back, a Theodor Seuss Geisel Honor Book; This Is Not My Hat, winner of the Caldecott Medal and the Kate Greenaway Medal; and We Found a Hat. He is also the illustrator of two Caldecott Honor books, Sam and Dave Dig a Hole and Extra Yarn, both written by Mac Barnett. Jon Klassen lives in Los Angeles.

Reviews

Square’s efforts to please are equal parts hilarious and cringeworthy, and the moment he topples over in exhaustion is comic gold. The story’s decidedly ambiguous conclusion leaves the door open for questions about what it means to be an artist—and that’s the whole point.
—Publishers Weekly (starred review)

This book takes a sweeter turn from its prankish predecessor in that Square works hard to create something for Circle, only to feel like he failed; but when Circle sees what he created, she is “beguiled” once more by his genius. Though this title will stand alone, children familiar with Triangle might recognize the extra layer of humor at the end when an unnamed narrator poses a game-changer of a question. A must purchase that will satisfy old fans and create new ones.
—School Library Journal (starred review)

Funny and lightly philosophical, Barnett’s story gets an extra punch of hilarity with Klassen’s minimalist graphite-and-watercolor artwork. A must for Triangle fans that will leave them wondering how this geometric drama will end.
—Booklist

With typically deceptive minimalism Klassen places a few flat, blocky shapes on the white pages to suggest the physical landscape, angling Square's body and glance to convey the emotional one. Humor is in the details: a bit of twig that catches on harried Square's head and stays there; the shadow that appears beneath Circle as she floats along through the air. For all its brevity, chockablock with philosophical topics to ponder and debate.
—Kirkus Reviews

Barnett’s text is funny and profound, raising philosophical questions about intent, genius, and truth. Klassen’s trademark eyes do a lot of emotive work amid the spare, fantastical set- ting. Angled lines (in the rocks, plants, and slanting rain) and white space direct readers’ own eyes across each page or spread, and short sentences, smart dialogue, and word repetition keep the story moving at a steady pace. Readers looking for a compelling read-aloud will not be disappointed.
—The Horn Book

There’s a ’60s flair to this story of friendship and artistry; the text is spare yet robust, with a lot of meaning behind the carefully selected words, and the open-ended conclusion will give kids much to discuss. Klassen’s watercolor, graphite, and digital art is animation ready, with simple textured shapes against white backgrounds...While the story could provoke discussions about expectations and friendships, this title is most at home as an original entry in art curricula.
—Bulletin of the Center for Children's Books

Square attempts to make a Circle sculpture that will be as perfect as his friend is...Children will no doubt find the results hilarious. The droll illustrations by the Niagara Falls, Ont., native Klassen, in subtle shades of gray, brown and blue, endow these friends with personality and Barnett's simple text is perfect.
—The Buffalo News

Droll, subdued and enigmatic, this second volume of a planned trilogy will delight children ages 5-9.”
—The Wall Street Journal