Max Tyne's advancing age and waning health were adding urgency to his struggles with the design for the engines which would power a new class of space vessel. The greatest scientist of his generation, Tyne was the undisputed father of the colonisation of space. He was to drive the future, but not before the future had driven him. The Calliope, a Spacity, as big as a large terrestrial city, is on a mission to survey possible routes through Earth's corner of the galaxy. But Walter Potter, a medical orderly on the voyage, is increasingly doubtful that this is just a simple survey patrol. With a small group of friends, he sets about trying to solve the mystery behind their mission, and comes finally, to answers beyond his wildest imaginings. This is a story of fictional science, the blending of science fact with meticulously constructed science future, in a tale rich in characters and action. A story to entertain, to inform and to set the imagination running.