Past tense? So the danger's passed? Of course not. Synop:

Terrifying disturbances have been reported in the Uranium mines of Fortuna. The minors have come to believe that they are haunted, and the delays in production have attracted the attention of the Royal Atomic Energy Commission. Their agent arrives to discover one of the mine's owners, a young woman of unknown origin, living in terror of the other, an old man with mad dreams of immortality.

They follow a mysterious and ruthless would-be goddess into another world, where masked beings of pure energy have enslaved the population for thousands of years, drawing their titanic power from the unfathomable Well of the Worlds.

And then it gets weird. But readers expecting giant torpedo-headed creatures whipping masses of humanity off a cliff for some reason will be disappointed.