'High above them, Lora and Clyde heard a sound their world had not heard for centuries - the thin scream of a starship coming in from outer space, leaving a long white tail like smoke across the clear blue sky. They looked at each other in wonder. After three hundred years of silence, Earth had reached out once more to touch Thalassa . . .' And with the starship comes knowledge, and love, and pain. In these five science-fiction stories Arthur C. Clarke takes us travelling through the universe into the unknown, but always possible future.