The menace is invisible. The danger is not. Only one boy has the imagination to see the truth. Facing an invisible enemy, Bertie 'H. G.' Wells discovers that imagination isn't just escape - it's power. And it might just save Victorian London. Thirteen-year-old Bertie is tired of being told he's too frail for adventure, until a bandaged stranger demands jars from his family's struggling shop, sweeping him into a mystery that could destroy the Crystal Palace's dazzling Age of Innovation Exposition. When objects fly and shops are smashed by unseen forces, Bertie is blamed. To clear his name, he must gather an extraordinary band of allies, guided by the creator of Sherlock Holmes. London is under attack, and only one boy can see the danger.