Eden Colony. The surface hides under a thick cloud blanket, thrown up by the terminal war. The aliens came out of nowhere and their invasion spread so rapidly that nobody knew how to stall it. The off-world relief forces had no time to form, and in the end, the only weapons that could destroy the aliens destroyed civilization as well. But that was a long time ago. Probes report that the planet is now inhabitable, and there are powers that have vesting interest in returning...
Note: This is a programmed adventure, but several players may play it if one of them is willing to act as the Game Master.