His first book as Robert Charles was 'The Faceless Fugitive' (1963) and up to 2010 he had written 33 novels as such with Blood and Sangria (2010) being the last one.
As Charles Leader he first published 'Frontiers of Violence' (1966) and wrote 17 books under that pseudonym up to 1978, the last being 'Kingdom of Darkness' (1978).