The bases of the major powers are watching one another—and waiting...

But what bothers Britain’s Moon Base personnel most of all is the visit of a Royal Commission, sent to investigate expenditure. Travelling with the Commission, but under separate secret orders, is Felix Larsen, whose investigations are of quite a different nature.

Why should one man fall a thousand feet and escape with minor bruises while another dies after falling eighteen inches? Why does a desperate man, bent on suicide, find it absolutely impossible to kill himself? What are the strange messages emanating from the Base—and where do they come from? And what is the fantastic thing that has been conceived in the research department?