It was just a smooth round metal ball, less than a metre in diameter.Although it was still hot from its journey through the hugenothingness of space, it looked quite harmless. But what was it,exactly? A meteor, perhaps - just one of those pieces of rock fromouter space that occasionally fall down on to the planet Earth. Butmeteors don´t usually make strange hissing sounds . . . In thiscollection of four of his famous science-fiction stories, John Wyndham creates visions of the future that make us think carefully about theway we live now.