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?