"Jonah Winter’s honest depiction, accompanied by the vivid and detailed artwork, tells the creation of the atomic bomb with expertise and tact... This is an excellent historical, as well as scientific, picture book offering opportunity for rich discussion among student readers and educators. Highly Recommended."

– School Library Connection, May/June 2017

"An author’s note supplies more information about the event and its repercussions, but the text itself, concise and thorough, stands on its own, its dispassionate accounting just the right counterpoint to the contained terror in the art."

– The Horn Book *STARRED REVIEW*, March/April 2017

"A picture book’s powerful potential to reach multiple audiences at varied levels of prior knowledge and understanding is on full display here, and adults tasked with shepherding youth of all ages through the darkest episodes of history will appreciate so moving and versatile a guide. The youngest audience will learn the facts, but the sinister implications a secret government project and the unimaginable consequences of covert research will impel an older readership to confront their grim inheritance."

– Bulletin of the Center for Children's Books *STARRED REVIEW*, January 2017

"Sure to spark conversation about ethics and the use of nuclear weaponry, this powerful book demands a wide readership."

– Publishers Weekly *STARRED REVIEW*, 12/5/16

"[T]he quiet—and then abruptly explosive—tone is spot-on, cultivating both curiosity and unease, as if this is a secret we’d rather not know. Expect plenty of questions after sharing this with children, though it’s likely that’s precisely the point."

– Booklist *STARRED REVIEW*, 12/1/16

"Jonah Winter's text is eloquent, and his mother's acrylic-and-pen illustrations evoke a beautiful landscape in danger if the scientists' contraption works.... An astonishing way to lay the groundwork for such works for older readers as Steve Sheinkin's Bomb (2012), this is a beautifully told introduction to a difficult subject."

– Kirkus Reviews *STARRED REVIEW*, 11/1/16

A moving, nonpreachy springboard for older elementary grade and middle school discussions of the Manhattan Project or nuclear weapons in general.

– School Library Journal, January 2017