Sparrow’s comic fantasy epic, about a boy from our world summoned into a magical realm ruled by a despotic lime, pulls off the difficult trick of simultaneously parodying, celebrating, and exemplifying its genre. Nebraska teen Gilbert, a lover of all things fantasy, gets pulled—along with a tree named Tree—into a world riven by a fissure called the Great Splat, where everyone has names like Bundersquash Borum Balbagoose the Studious. Gilbert’s summoners had hoped the spell that transported him would bring instead the chosen one of prophecies, but to everyone’s surprise, especially Gilbert, the magic instead has brought them a fictional character—our Earth, it turns out, is a realm invented in theirs by a decidedly unpopular fantasy author. Still, as the tyrant Obble Dor Hobblebosh shuts down magic on his half of the world, Gilbert, drawing on his knowledge of how fantasy stories work, convinces wizards and leaders that maybe he could prove the hero they need. After all, Hobblebosh’s anti-magic spells only affect people on their world’s “roster”—not made-up interlopers. Sparrow excels at playful chatter, worldbuilding, genre-specific meta-fiction, and general inventive nonsense worthy of Terry Pratchett, such as a list of fantasy-world boy bands or a pygymy minotaur zipping about on a parakeet. The prose is crisp, fleet, and witty, often driven by truly funny dialogue. What’s most surprising, though, is the depth this dauntingly long novel develops as the adventure goes on. Much like in the hobbits stories long loved by Gilbert—now Gigglebrit Maistowne Nebraska the Fictional—the quest will feature failure, loneliness, loss, hard choices, and the sundering of a fellowship. Sparrow commits to characters readers will care about, even if apparently ridiculous at first, and at making the magic system make sense. Some passages of protracted silliness, especially an early tour of a wizards’ tower, work against that urgency, though the balance is righted in the novel’s more gripping second half. Readers will not possibly guess at how much trouble a tree from our world can stir up in fantasyland. Takeaway: Hilarious epic fantasy blending playful parody and a zest for adventure.