Karl Neder - physicist, socialite and all-round agent provocateur - thinks he has made a discovery that will offer mankind energy for free. But no one believes him - or rather, no one understands him. And so he is forced to wander like a vagabond across Cold War Europe, an outcast from his native Hungary, leaving chaos and half-built machines in his wake. But who, and where, exactly is Karl Neder now? Young journalist Lena Romanowicz wants to find out, hoping to kick-start a stalled career but driven more by motives she would rather not interrogate. Yet to understand Karl Neder she must wrestle with his story, which ranges from the castles of Transylvania to the rocket labs of NASA, from Viennese cafes to the blasted borderlands of the Soviet Union. Here is a Geiger-counter of a novel that crackles with ideas and shines a bright, brilliant light on the history of science and ideas, and on the fate of would-be geniuses who challenge the orthodoxy of their time.