ALA Booklist (Fri Nov 01 00:00:00 CDT 2013)

McKinley's distinctive voice instantly draws the reader into an alternative America where magic, once fairly commonplace, has been genetically removed from the population. Although the government attempts to control magic with science, there are still collisions and unexplained breaks between worlds that release strange energy and beings into Newworld. Our narrator and guide is Maggie, whose mother has gotten remarried to an Oldworlder named Val. Val is accompanied by creepy shadows only Maggie can see, which makes her dislike her stepfather even more. She works after school at an animal shelter, and it is her intense love of animals that helps unravel the multiple plot threads, which include several romances and origami that can contain magical outbreaks. Fascinating backstories reveal that magic isn't as dead in Newworlders as the government would like everyone to believe. Maggie's wry and witty conversational tone is an excellent vehicle for relating her fantastic yet logical adventures. McKinley's smooth but swift pace sets the stage for a welcome sequel.

Kirkus Reviews

Insanely detailed, sometimes confusing, ultimately rewarding; in other words, classic McKinley. This book is not the eagerly anticipated follow-up to Pegasus (2010). The sooner readers get past that, the sooner they can dive into the stream-of-consciousness, first-person narrative, which rushes along despite the fact that not very much happens for quite a while. Magic versus science: In Maggie's world, an alternate Earth, civilized countries like the U.S. are Newworld, all science all the time, while everyone else is Oldworld, magic steeped and probably pretty dreeping awful. McKinley shines when she invents new worlds, slang and all, and she is clearly having some fun with her bright but cranky teen heroine. Maggie unexpectedly finds herself, her unusual algebra book, her motley friends and lots of critters (both origami and real) caught in the middle of a massive "cohesion break" that could destroy the world. Newworld Maggie, who sees shadows around her secretly-a-magician Oldworld stepfather, might be in a position to save everyone, which provides some action in the second half, but this is a slow, immersive read despite the high stakes, more concerned with family and friendship than pacing. McKinley's writing is an acquired taste. While this is not the book to start with, for those who have already fallen under her spell, it's bound to appeal. (Fantasy. 12 & up)

School Library Journal (Sun Dec 01 00:00:00 CST 2013)

Gr 8 Up-This fast-paced novel is set in Newworld, where magic is illegal and individuals who carried the gene for it had their DNA modified several generations ago. Teenager Maggie is still reeling from the death of her father when her mother falls in love with a mysterious man, Val, who's from Oldworld, where magic is still used. However, it's the shadows that follow Val that worry her and not just the fact that her mother has moved on. Soon after meeting Casimir, a cute, recent immigrant from Oldworld, things really start to get strange. When a "cobey," a dangerous gap in reality, opens up at a local park, Maggie instinctively closes it by making origami talismans out of pages from her math textbook. Once her mother and stepfather finally reveal their own histories with magic, Maggie is exposed to a side of the world she didn't know existed. This fantasy focuses on the relationships among characters. There is enough Newworld vocabulary to create and support the strange and enchanted setting, but not so much as to confuse or frustrate readers. Shadows is a dense book in parts, but teens will be motivated to keep reading by the exciting action, lovable characters, and witty dialogue. Sunnie Lovelace, Wallingford Public Library, CT

Horn Book (Tue Apr 01 00:00:00 CDT 2014)

Newworld, Maggie's home, is science-driven; magic, fairy tales, and fantasy are all frowned upon, which is why the mysterious, sentient shadows that surround Maggie's stepfather are troubling--as is Maggie's ability to see them. Maggie is a sardonic and sharp narrator. McKinley's skill at building memorable worlds is also evident: Newworld itself is as intriguing as the characters.

Publishers Weekly (Fri Oct 06 00:00:00 CDT 2023)

McKinley (Pegasus) introduces a modern civilization much like our own, but in which Oldworld (roughly Europe) is magical, while Newworld (approximately North America) has embraced science and genetically engineered its citizens to be free of magic. Both worlds, however, are subject to cobeys (cohesion breaks)-interdimensional storms that can produce earthquakelike destruction, or worse. Maggie, a typical 17-year-old, loves animals, origami, and boys, but is upset because her widowed mother has remarried a man named Val, an Oldworlder (-I-ve seen orangutans that wore clothes better,- Maggie gripes). Val was supposedly stripped of magic before immigrating to Newworld, so why can Maggie see a terrifying thicket of shadows around him? And why are they trying to communicate with her? McKinley-s characters and dialogue make this novel a joy: Maggie is a brash yet vulnerable protagonist, and her family, Val, and two possible boyfriends (both of whom may be magical) are well developed. The magic system isn-t all that fleshed out, but the culture of Newworld is a fascinating amalgam of the everyday and the strange. All in all, a delightful read. Ages 12-up. (Sept.)