Bob Shaw\'s novel chronicles the adventures of the crew of the survey ship Sarafand, whose mission is to explore and map newly-discovered planets. In the course of their travels they encounter many startling forms of life and alien menaces. On one world, the ship sends out its six survey modules, only to have SEVEN return. One of them is actually an intelligent, malevolent alien, able to change its shape at will... but how can they identify which module is the impostor? Part of the highly collectible \"yellow jacket\" Gollancz SF series, this first edition book is as new, excepting a slightly faded spine on the dust jacket.