It was just a smooth round metal ball, less than a metre in diameter. Although it was still hot from its journey through the huge nothingness of space, it looked quite harmless. But what was it, exactly? A meteor, perhaps - just one of those pieces of rock from outer space that occasionally fall down on to the planet Earth. But meteors don't usually make strange hissing sounds . .. In this collection of four of his famous science-fiction stories, John Wyndham creates visions of the future that make us think carefully about the way we live now.