A four hundred year journey through space is about to end for the teeming inhabitants of a large ship-world. The air is thick with expectation as they enter the system that is to become their new home, the probes reporting nothing more advanced than bacteria and algae among the clustered planets. But the original data was wrong, and direct scans of the planet reveal a whole alien civilisation. Maybe the aliens have just arrived. Maybe evolution has been incredibly rapid during their long journey ... Neither of these explanations seem plausible. It seems likely that the probe data has been falsified from the beginning. Advice is years distant, help is decades away. They're on their own and they'll have to decide a plan of action fast as the rest of humanity is just as vulnerable and not much further away.