All communication with the Nocturnal Moonbase has been lost, and the rescue party sent to investigate has not returned.

A second party is collected and includes Professor Abbacus, Alice and Andre. They travel to the Moonbase to find it airless but not abandoned. A nasty surprise within leads them down into a grim realm not even the genius Abbacus realised existed.

But from this dark place the party travels to a world the Professor knows all too well. It is a world within a world of strange, prehistoric creatures, beastmen, ancient temples and shining cities inhabited by godlike beings.

It is also a world of dark secrets, abandoned friends and old enemies. One being in particular has been waiting over a century for Professor Abbacus to return so he can have his final revenge upon him.