Impossible Creatures by Katherine Rundell Review: A Landmark Fantasy Series Opener

Christopher Forrester, a boy from the ordinary world, travels to stay with his grandfather in Scotland, ventures up a forbidden hill, and discovers that his family are guardians of the passage to the Archipelago — a cluster of unmapped islands where magical creatures have thrived for thousands of years, sustained by glimourie, the world's magic, which flows from the Glimourie Tree at the Archipelago's heart. There he meets Mal Arvorian, a girl from the islands who is in possession of a flying coat and a baby griffin and is being pursued by a murderer. Together they embark on an urgent quest across the Archipelago — consulting sphinxes, battling kraken, negotiating with dragons, and travelling with a part-nereid woman, a ratatoska, and a Berserker — to find the Immortal, the only being capable of reversing the draining of the glimourie. As one passage the book itself puts it, their journey is driven by the desire "to protect something worth protecting" and an "insistence that the world is worth loving." The novel's central stakes are clear and large: if Mal and Christopher fail, the magic of the world — and the creatures that depend on it — will be lost entirely.

Impossible Creatures represents a deliberate departure for Rundell: it is her first work of full fantasy, and her sixth novel for middle-grade readers. As critics noted, her previous novels contain fanciful elements, but this is the book where she steps fully into the tradition of Oxford's illustrious children's fantasy authors — a tradition that has prompted critics to place her alongside Tolkien and Lewis. Rundell is a Fellow of St. Catherine's College, Oxford, and her non-fiction biography of John Donne, Super-Infinite, won the Baillie Gifford Prize; she has also received the British Book Award for Book of the Year and Author of the Year. Impossible Creatures became an instant bestseller in Britain upon its original publication and won the Waterstones Book of the Year. Philip Pullman, whose His Dark Materials trilogy is the most direct touchstone for the book's dual-protagonist structure and themes of sacrifice, described Rundell as "a writer with an utterly distinctive voice and a wild imagination."

The novel's worldbuilding is one of its most praised qualities. Its Archipelago is populated with an inventive bestiary — sphinxes, kraken, ratatoska, dragons, centaurs — and the book includes more than 60 illustrations by Ashley Mackenzie, a map, and a full bestiary of magical creatures, giving the world a physical and visual density. Critics praised the book as "brimming with intelligence, inventiveness and generosity of heart," and Kirkus Reviews highlighted Rundell's skill in equipping her protagonists with both tangible tools — a casapasaran that always points home, a glamry blade that cuts through anything — and intangible ones rooted in moral conviction. Rick Riordan, author of the Percy Jackson series, recommended it heartily to readers of all ages, particularly animal-lovers, lovers of magic, and fans of fairy tales. Critical coverage, in assessing Rundell's broader body of work, identified her grand theme as "the vital necessity of wildness" — a description that fits Impossible Creatures precisely.

For all its ambition, the book is not without its tensions. Critics observed that action, not awe, is Rundell's strong suit — the novel moves at pace and prioritises momentum over contemplative wonder, which may disappoint readers expecting the languorous world-immersion of Tolkien. Kirkus Reviews, while awarding the book a starred verdict and a place on its Best Books list, also noted in a separate assessment that the novel can be "ultimately more than a little full of itself" — a fair caution for readers wary of epic fantasy that wears its grand themes conspicuously. The novel's scale and the density of its creature-lore and quest-structure also mean it rewards committed readers willing to track a large cast and accumulating mythology; younger or more casual readers at the lower end of the recommended age range may find the complexity demanding.

Kirkus Reviews places the book squarely in the 10–16 age range, and the publisher recommends it for readers from Grade 5 upward. It is designed for young readers ready for a serious, fully realised fantasy series — one with real stakes, moral weight, and a protagonist duo structured, as Kirkus observed, in the tradition of Lyra and Will from Pullman's His Dark Materials, sacrificing innocence for experience. Adults who read widely in children's fantasy will find it equally rewarding; Riordan explicitly recommended it to readers of all ages. As the first of three books, it is an ideal entry point for readers looking to invest in a new long-form fantasy world — one that arrives already validated by major critical recognition and a robust reception on both sides of the Atlantic.