The passenger liner the Star Queen, suffered mysterious damage to its jump engines and emerged from hyperspace, close to the sun, at half-light speed on a collision course with Earth. Distress signals were sent out as the ship scorched into the Earth's atmosphere to explode devastatingly just before impact. 600 years later, and 600 light years away, the distress call is intercepted by a warship of Her Majesty's Star Fleet. The distress call is a radio signal, presumably because of an FTL coms failure, and it is soon realised that its origin is the start of the twentieth century, before space travel was discovered.