One morning Sam wakes up to see strange vessels gathered in the skies around London. As he stares up, people stream past him, walking silently towards the enormous ships which emit a persistent noise. Only Sam seems immune to the influence of this signal, but when drones swoop down hunting for resisters, Sam is saved by a group of kids who, like him, have escaped the strange enslavement. Using their wits, some captured alien technology and the resources of Earth's governments - now at their disposal - they must find out who controls these ships, what they want, and how to stop them. A fabulously plotted encounter of the third kind from a master of adventure fiction.