From the back cover:
“The Venus Adventure, fraught with prehistoric dangers on a Dawn World still trembling to the tread of the dinosaur – the Venus Adventure has been successfully concluded.
“Once again, on Terra, the Peacelord of the Universe can turn his attention to the problems of the New Power.
“But now, on Earth, a new crisis arises: from out of nowhere materializes an evil mastermind.
“To Perry Rhodan as Moriarty to Sherlock Holmes, as Duquesne to Richard Seaton. A villainous figure, intent on undermining the progress of the New Power! A super-hypnotist who enslaves the minds and bodies of his own band of mutants and sets them against Perry and his futuremen in a war of wills that produces new thrills and chills for Rhodan and his readers in –
“Menace of the Mutant Master.”
For my comments and reactions to this book, and other features in this 1972 paperback version of a sci-fi pulp magazine, including an unauthorized presentation of the foreword by Ray Bradbury in toto, see here.